Clinical outcomes of limited-open retrograde intramedullary headless screw fixation of metacarpal fractures

Advances in the Treatment of Hand and Wrist Injuries in the Elite Athlete

Caring for hand and wrist injuries in the elite athlete brings distinct challenges, with case-by-case decisions regarding surgical intervention and return-to-play. Metacarpal fractures, thumb ulnar collateral ligament tears, and scaphoid fractures are common upper-extremity injuries in the elite athlete that can be detrimental to playing time and future participation. Treatment should therefore endure the demand of accelerated rehabilitation and return-to-activity without compromising long-term outcomes. Fortunately, the literature has supported emerging management options that support goals specific to the athlete. This review examined the advances in surgical and perioperative treatment of metacarpal fractures, thumb ulnar collateral ligament injuries, and scaphoid fractures in the elite athlete.

Complications of osteosynthesis for long-finger metacarpal and phalanx fracture

Fractures of the metacarpals and phalanges represent a significant proportion of hand fractures. Although non-operative treatment is generally effective, some fractures require surgery. Historically, osteosynthesis using K-wires was widely used, but screw plates and then cannulated intramedullary screws have emerged as therapeutic alternatives. We assessed the complications associated with the different osteosynthesis techniques: stiffness, infection, bone consolidation and hardware-related problems. Each osteosynthesis technique has advantages and disadvantages, and choice depends on several factors. An individualized approach according to patient and fracture is essential to optimize clinical results.

Screw Position Following Percutaneous Versus Mini-Open Intramedullary Retrograde Screw Fixation of Metacarpal Fractures

BACKGROUND

Metacarpal fracture fixation using the retrograde intramedullary screw technique can be performed through two different approaches. The mini-open approach requires greater soft tissue dissection but allows for direct visualization of the metacarpal head compared with the percutaneous approach. Our aim was to determine which approach resulted in optimal screw position.

METHODS

Eighty-one consecutive patients that underwent intramedullary screw fixation for metacarpal fractures from 2016 to 2021 were identified. Patients were treated by 4 fellowship-trained orthopedic hand surgeons who employed the mini-open or percutaneous approach. Postoperative radiographs were reviewed for screw position.

RESULTS

A total of 81 patients (41 mini-open, 40 percutaneous) were included in this study. There were no significant differences between the two groups in age, sex, hand dominance, or affected digit. Postoperative screw position at first postoperative visit was not significantly different between the two groups on anteroposterior or lateral radiographs.

CONCLUSION

Postoperative screw position is not significantly different between the mini-open and percutaneous approaches for intramedullary screw fixation of metacarpal fractures.

LEVEL OF EVIDENCE

Level III, therapeutic.

Early Return of Motion in Patients With Intramedullary Screw Placement for Metacarpal and Phalangeal Fracture Fixation

INTRODUCTION

Hand fractures are associated with significant morbidity. Current management standards often result in prolonged immobilization, stiffness, and delayed return to functional use. Intramedullary (IM) compression screws offer minimal soft tissue disruption and early postoperative active motion. In this study, we describe our outcomes after intraosseous fracture fixation using IM cannulated headless screws for a multitude of fracture patterns.

METHODS

This study is a retrospective review of patients who underwent IM screw placement for fixation of metacarpal and phalangeal fractures by a single surgeon from 2017 to 2022. Data were collected to include patient demographics, fracture details, postoperative complications, and follow-up. Time to range of motion and return to unrestricted motion was recorded.

RESULTS

There were 69 patients with 92 fractures (n = 54 metacarpal, n = 38 phalanx). The median patient age was 45 years (range, 18-89 years) with 75.4% males. Majority presented with a single fracture (n = 50, 72.5%), and 38 patients (55.1%) had open fractures. Small finger was the most affected digit (n = 35, 37.6%). The median time to allow range of motion from surgery was 8.7 days (interquartile range, 0-32) with 32 days (interquartile range, 10-62) for unrestricted use of the hand. Thirty-five patients (50.7%) were allowed controlled motion from the first postoperative day. One patient had loss of reduction requiring reintervention for hardware removal, and 1 patient had superficial skin infection managed with oral antibiotics.

CONCLUSIONS

Our findings indicate that the IM screw provides reliable fixation for a wide variety of fracture patterns with a low complication rate and offers early return to functional use.

Comparison of Intramedullary Screw Fixation, Plating, and K-Wires for Metacarpal Fracture Fixation: A Meta-Analysis

BACKGROUND

Metacarpal fractures are common injuries with multiple options for fixation. Our purpose was to compare outcomes in metacarpal fractures treated with intramedullary screw fixation (IMF), Kirschner wires (K-wires), or plating.

METHODS

A systematic literature review using the MEDLINE database was performed for studies investigating metacarpal fractures treated with IMF, plating, or K-wires. We identified 34 studies (9 IMF, 8 plating, 17 K-wires). A meta-analysis using both mixed and fixed effects models was performed. Outcome measures included mean Disabilities of the Arm, Shoulder, and Hand (DASH) scores, total active motion (TAM), grip strength, time to radiographic healing, and rates of infection and reoperation.

RESULTS

Patients with IMF had significantly lower DASH scores (0.6 [95% confidence interval [CI], 0.2-1.0]) compared with K-wires (7.4 [4.8-9.9]) and plating (9.8 [5.3-14.3]). Intramedullary screw fixation also had significantly lower rates of reoperation (4%, [2%-7%]), compared with K-wires (11% [7%-16%]) and plating (11% [0.07-0.17]). Grip strength was significantly higher in IMF (104.4% [97.0-111.8]) compared with K-wires (88.5%, [88.3-88.7]) and plating (90.3%, [85.4-95.2]). Mean odds ratio time was similar between IMF (21.0 minutes [10.4-31.6]) and K-wires (20.8 minutes [14.0-27.6]), but both were shorter compared with plating (52.6 minutes [33.1-72.1]). There were no statistically significant differences in time to radiographic healing, TAM, or rates of reoperation or infection.

CONCLUSIONS

This meta-analysis compared the outcomes of metacarpal fixation with IMF, K-wires, or plating. Intramedullary screw fixation provided statistically significant lower DASH scores, higher grip strength, and lower rates of reoperation, suggesting that it is a comparable method of fixation to K-wires and plating for metacarpal fractures.

Metacarpal Shortening with Intramedullary Screw Fixation: A Cadaveric Study

Background  Intramedullary screw fixation is a commonly used technique for the management of metacarpal fractures. However, compression across the fracture site can lead to unintentional shortening of the metacarpal. Questions/Purposes  Our aim was to evaluate the risk of overshortening with differing intramedullary device designs for fixation of metacarpals. Methods  The small finger metacarpal of nine fresh-frozen cadavers were included. A metacarpal neck fracture was simulated with a 5-mm osteotomy. Three different intramedullary screw designs were compared. Each screw was placed in a retrograde fashion into the intramedullary canal and the amount of shortening measured. Screws were reversed and the number of reverse turns with the screwdriver needed to release overshortening were measured. Results  The average shortening at the osteotomy site was 2.5 mm. The mean shortening was 80%, 58%, and 12% for the partially threaded screw, fully threaded screw, and threaded nail, respectively. The mean differences of the distance shortened were statistically significant for the threaded nail compared with the partially and fully threaded screws. The partially threaded screw had the most shortening, while the threaded nail provided the least amount of shortening. When the screws were reversed, the screws did not disengage until the screw was fully removed from the osteotomy site. Conclusion  The fully threaded nail demonstrates less shortening and possibly minimizes overshortening of fractures compared with partially threaded and fully threaded screw designs. Overshortening cannot be corrected by unscrewing the screw unless completely removed from the distal fragment. Clinical Relevance  Orthopaedic surgeons may select intermedullary screws based on the design that is suited for the particular metacarpal fracture pattern.

Intramedullary Fixation of Hand Fractures and Arthrodeses

Intramedullary fixation has long been popular for fracture fixation in the upper extremity from the shoulder through the carpus. Recently, intramedullary fixation in the hand has gained increasing interest, specifically in the metacarpals and phalanges, corresponding with the development of improved cannulated headless screw technology. Along with the advantages of increased operative speed and less surgical dissection, which can promote rapid healing, many benefits exist, supporting their use despite some drawbacks. This article reviews the background and biomechanics of intramedullary fixation with a specific focus on cannulated headless screws, describes the application and techniques of intramedullary screw fixation in the hand, and details the associated outcomes and costs for metacarpal fractures, phalangeal fractures, and interphalangeal joint arthrodesis.

Outcomes Following Fully Threaded Intramedullary Nailing of Metacarpal Fractures

Purpose

Intramedullary screw fixation has emerged as a popular approach for the treatment of displaced metacarpal fractures. The purpose of this study was to investigate the functional and radiographic outcomes of a newly designed, headless noncompressive fully threaded intramedullary nail (TIMN) for the treatment of metacarpal fractures.

Methods

A retrospective chart review was performed on patients who were treated with the INnate TIMN (ExsoMed) at a single academic institution with a minimum of 1-year follow-up. Patient-reported functional outcomes included Quick Disabilities for the Arm, Shoulder, and Hand (QuickDASH) questionnaires, return to work and physical activity time, and overall satisfaction. Radiographs were retrospectively reviewed to determine radiographic union, change in angulation, and metacarpal shortening.

Results

A total of 49 patients (58 fractures) with a mean age of 36 years (range: 17-75 years) were included. The mean follow-up time was 2.7 years (range: 1.4-4.3 years). Overall, the mean patient satisfaction rating was 4.9 of 5 (range: 3-5). The mean return to work time was 7.2 weeks (range: 0.14-28 weeks), and the mean return to sport or activity was 8.3 weeks (range: 1-28 weeks). Average QuickDASH scores across all patients were 4 (range: 0-56.9). The median radiographic healing time was 6.1 weeks (range: 4.7-15.4 weeks). Mean postoperative shortening in the fifth metacarpal fracture was 3 mm (range: -4.2 to 8 mm) at the initial postoperative visit and 3.6 mm (range: -3.3 to 7.9 mm) at the final radiographic follow-up. Subgroup analysis showed that postoperative shortening was similar, regardless of the fracture pattern. The following four complications were reported: one case of persistent pain and stiffness, one case of carpal tunnel syndrome, one nonunion, and one fractured intramedullary nail.

Conclusions

Our findings suggest that the TIMN allows for a reliable return to work and physical activity, high patient satisfaction, low complication rate, and minimal shortening at the final radiographic follow-up.

Type of study/level of evidence

Therapeutic IV.

Articular Involvement With Retrograde Headless Compression Screw Fixation of the Metacarpal

PURPOSE

Retrograde headless compression screw (RHCS) fixation for metacarpal fractures can lead to metacarpal head articular cartilage violation. This study aimed to quantify the articular surface loss after insertion of the RHCS and determine the functional range of motion (ROM) of the metacarpophalangeal (MCP) joint at the point of contact between the proximal phalangeal (P1) base and the articular defect.

METHODS

Ten fresh-frozen cadaveric hand specimens were analyzed for prefixation MCP joint ROM. After screw insertion, the ROM at which the dorsal portion of the P1 base begins to engage the screw tract defect, as well as the ROM at which the midsagittal portion of the P1 bisector engages the screw tract defect, was recorded. The distal axial articular surface of the metacarpal and the defects from screw insertion were measured using a digital image software program.

RESULTS

Nine men and one woman (mean age, 69 years) were examined. The prefixation mean extension-flexion arc for all MCP joints ranged from 1° to 85°. After screw insertion, the mean MCP ROM at which the dorsal P1 articular surface first engaged the screw tract was 31°. Only 7 digits had screw tract engagement with the midsagittal bisector of the P1 base at a mean flexion angle of -18° (18° hyperextension). Mean articular surface violation increased from the index finger moving ulnarly, with an average of 3.9% involvement.

CONCLUSIONS

Articular surface loss of the metacarpal head following RHCS insertion is negligible in a cadaveric model, with minimal engagement between the corresponding defect and the P1 base during functional ROM.

CLINICAL RELEVANCE

Retrograde headless compression screw fixation of metacarpals inevitably damages the cartilage. However, the actual defect is small in proportion to the articular surface area and not engaged during functional activity. These biomechanical features may mitigate the surgeon's concern about joint destruction, while ensuring the benefits of early rehabilitation and minimal invasiveness of this technique.

Intramedullary K-wires versus Alternate Techniques for Metacarpal Shaft and Neck Fractures: A Systematic Review and Meta-analysis

Intramedullary K-wire (IMKW) fixation is one of the mainstays for surgically treating metacarpal shaft and neck fractures. However, there remains a lack of literature comparing outcomes of the various available surgical repair techniques in all indicated metacarpals. Therefore, we conducted a systematic review and meta-analysis to investigate the clinical advantages and drawbacks of IMKW compared with alternate fracture repair techniques. A comprehensive systematic literature review was performed to identify studies that compared clinical outcomes of IMKW to alternate metacarpal fixation modalities. Outcomes included Disabilities of the Arm, Shoulder, and Hand (DASH/ quick DASH) scores, grip strength, union rate, visual analog scale pain, operative time, and complications. A random-effects model was used to compare IMKW to the pooled effect of other fixation techniques. A total of 10 studies were included in our analysis, comprising 497 metacarpal fractures (220 shafts and 277 necks). IMKW fixation was identified as the control group in all studies. The pooled experimental group included plates, transverse K-wires (TKWs), interfragmentary screws (IFSs), and K-wire cross-pinning (CP). In treating metacarpal shaft fractures, IMKW showed significantly shorter operative time ( p  = 0.04; mean difference = - 13; 95% confidence interval = -26 to -0.64). No significant differences were observed in treating metacarpal neck fractures for disability, grip strength, healing rate, pain, operative time, or complication rate. This systematic review and meta-analysis found no difference in clinical outcomes among various surgical techniques for treating metacarpal shaft and neck fractures. Further high evidence studies are required that investigate the efficacy and safety of IFS, CP, TKW, and intramedullary screws versus IMKW for treating closed, unstable metacarpal fractures.

Intramedullary Screw Fixation of Metacarpal and Phalangeal Fractures

Metacarpal and phalangeal fractures are the second and third most common hand and wrist fractures seen in the emergency department. There are a multitude of operative fixation methods for metacarpal and phalangeal fractures, including closed reduction percutaneous pinning, open reduction internal fixation, external fixation, and intramedullary screw fixation. Although intramedullary fixation is a relatively new surgical technique, it is gaining in popularity as it allows patients to resume range of motion early in the postoperative period with excellent clinical outcomes.

Prospective Comparison of the Early Outcomes of Headless Compression Screw and Percutaneous K-Wire Fixation in Metacarpal Fractures

PURPOSE

The study aimed to assess early clinical outcomes achieved by headless compression screws (HCS) in fixation of metacarpal fractures, and to compare them with outcomes of percutaneous K-wire fixation. The hypothesis was that HCS would show better arc of motion and superior early clinical outcomes.

METHODS

This was a randomized study of nonthumb metacarpal neck and shaft fractures. To compare the 2 surgical techniques, 23 patients treated for metacarpal neck and shaft fractures were divided into 2 groups: 11 treated with K-wire fixation and the other 12 with HCS fixation. We followed the patients for 12 weeks. The primary objective was to compare metacarpophalangeal arc of motion, and the secondary aim was to determine clinical union, radiographic union, and recovery time before returning to employment in the 2 groups.

RESULTS

At each follow-up visit, patients in the group treated with HCS had better metacarpophalangeal arc of motion than those treated with K-wire fixation. The HCS group showed a shorter time interval to return to work (at 3 weeks) and no complications, while the K-wire group had 1 pin track infection, which was treated with oral antibiotics and pin removal.

CONCLUSIONS

Compared with K-wire fixation, limited-open HCS fixation for metacarpal neck and shaft fractures was superior in terms of the early postoperative metacarpophalangeal arc of motion and return to work.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic II.

Intramedullary Fixation with Cannulated Screw After Resection of Enchondroma in the Hand: Technique Description and Case Series

Purpose

Enchondromas are primary, benign bone neoplasms that arise from intramedullary proliferation of hyaline cartilage cells. Slow and progressive in growth, enchondromas can lead to bone destruction, deformities, and fractures. The treatment of enchondromas remains controversial. We hereby describe the technique for bone fixation using headless intramedullary screws (HISs) after enchondroma resection in the long bones of the hand.

Methods

From January 2018 to June 2021, all patients treated with HISs after the resection of enchondroma of the hand were retrospectively assessed and included in the study. The series comprised four patients with a minimum postoperative follow-up period of 12 months. Postoperative functional results were measured according to Takigawa criteria and postoperative radiographic results were graded according to the Tordai system.

Results

After tumor resection and screw fixation, one patient had autologous bone grafting from the iliac crest, and another had the defect filled with calcium phosphate cement. All patients were followed up for at least 12 months, and the mean healing time of the pathologic fracture was 5 weeks. There were neither complications related to the procedure nor the need for a second surgery.

Conclusions

We describe the technique of intramedullary headless screws for bone fixation after enchondroma resection in the long bones of the hand, as well as the excellent functional, cosmetic, and radiographic results of four patients treated with the technique presented herewith.

Type of study/level of evidence

Therapeutic IV.

Complications Following Intramedullary Screw Fixation for Metacarpal Fractures: A Systematic Review

PURPOSE

There has been a recent increase in the use of intramedullary screws (IMS) for the surgical treatment of metacarpal fractures. While IMS fixation has been shown to produce excellent functional outcomes, postoperative complications have yet to be fully explored in a comprehensive way. This systematic review quantified the incidence, treatment, and results of complications following IMS fixation for metacarpal fractures.

METHODS

A systematic review was performed using PubMed, Cochrane Central, EBSCO, and EMBASE databases. All clinical studies that documented IMS complications following metacarpal fracture fixation were included. Descriptive statistics were analyzed for all available data.

RESULTS

Twenty-six studies were included: 2 randomized trials, 4 cohort studies, 19 case series, and 1 case report. Among the 1,014 fractures studied, 47 complications were reported across all studies (4.6%). Stiffness was the most common, followed by extension lag, loss of reduction, shortening, and complex regional pain syndrome. Other complications included screw fracture, bending, and migration; early-onset arthrosis; infection; tendon adhesion; hypertrophic scar; hematoma; and nickel allergy. Eighteen of the 47 (38%) patients with complications underwent revision surgery.

CONCLUSIONS

Complications following IMS fixation of metacarpal fractures are relatively uncommon.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

A Biomechanical Comparison of Fixation Techniques in Metacarpal Shaft Fractures

Background  Typically, metacarpal shaft fractures are treated with closed reduction percutaneous pinning, intramedullary nails, or plate fixation. Recently some surgeons have begun using intramedullary headless compression screws. Questions/Purposes  The purpose of this study was to compare intramedullary screw fixation to K-wire fixation, which is the standard of care in a transverse metacarpal midshaft fracture, using a cadaveric model. Our hypothesis was that intramedullary screw fixation would have a biomechanical advantage (higher stiffness and peak load to failure) when compared with dual Kirschner wire fixation of transverse metacarpal shaft fractures. Methods  Four-point bend testing was performed to compare stiffness and failure load values of seven paired 2nd and 3rd metacarpals instrumented with headless intramedullary compression screw fixation or Kirschner wire fixation. Similar testing was performed on 14 unpaired 4th metacarpals. Results  There was no significant difference in peak load ( p  = 0.60) or stiffness ( p  = 0.85) between fixation groups for the 2nd and 3rd instrumented metacarpals. For the instrumented 4th metacarpals, there was no significant difference in peak load ( p  = 0.14), but the stiffness was significantly greater ( p  = 0.01) for the compression screw group compared with the Kirschner wire fixation. Conclusions/Clinical Relevance  In this study, the load to failure was not different between the two fixation methods and likely both techniques can sustain physiologic loads needed for rehabilitation. The greater stiffness in the 4th metacarpal compression screw group may be related to the smaller canal morphology than in the 2nd and 3rd metacarpals. Larger diameter screws may be needed to obtain a better fit particularly in the 2nd and 3rd metacarpals.

Ideal Length and Diameter for Intramedullary Screw Fixation of Metacarpal Fractures: A Biomechanical Study

Purpose

This biomechanical study evaluated the effect of intramedullary screw diameter and length relative to 3-point bending force and torsional force when used to stabilize metacarpal shaft fractures.

Methods

Transverse osteotomies were made in the proximal metacarpal shaft in 36 middle finger metacarpal fourth-generation composite Sawbones. To compare screw diameters, antegrade intramedullary screws of 30-mm length were placed in 6 metacarpals, which included 4.7-mm Acutrak 2, Standard Acutrak 2 (4.0 mm), and Mini-Acutrak 2 (3.5 mm) screws. To compare screw lengths, metacarpals were fixated with Standard Acutrak 2 screws of 26, 30, or 34 mm in length, with screw tips bypassing the osteotomy by 6, 10, or 14 mm, respectively. A 6 degrees of freedom robot was used for torsional and 3-point bending testing.

Results

Increasing screw diameter demonstrated significant differences in both 3-point bending and torsional strengths. Maximum torsional loads were 69 Ncm (4.7-mm Acutrak 2), 45 Ncm (Standard Acutrak 2), and 27 Ncm (Mini-Acutrak 2) (P < .05). Loads to failure in the 3-point bending tests were 916 N (4.7-mm Acutrak 2), 713 N (Standard Acutrak 2), and 284 N (Mini-Acutrak 2) (P < .05). Differing screw lengths demonstrated significant differences with maximum torsional loads when comparing the 26-mm screws (22 Ncm) with 30- and 34-mm screws (45 and 55 Ncm, respectively) (P < .05). The 3-point dorsal bending strengths were significantly different between the 26-mm screws (320 N) and 30- and 34-mm screws (713 N and 702 N, respectively) (P < .05).

Conclusions

The results demonstrated significantly higher torsional strength and resistance to 3-point bending with larger intramedullary screw diameters. Further, when selecting the intramedullary screw length, the screw tip should pass at least 10 mm beyond the fracture.

Clinical Relevance

This study provided biomechanical evidence to guide surgeons in selecting intramedullary screw diameter and length for treating metacarpal fractures.

Threaded Intramedullary Nails Are Biomechanically Superior to Crossed K-wires for Metacarpal Neck Fractures

BACKGROUND

Intramedullary nail (IMN) fixation of metacarpal fractures is an alternative to Kirschner wire (K-wire) fixation. The goal of this study was to compare the biomechanical properties of K-wire fixation with a threaded IMN (InNate; ExsoMed, Aliso Viejo, California).

METHODS

The study design was based on previously described biomechanical models for evaluating metacarpal fractures. Sixteen fresh frozen small finger-matched and ring finger-matched pairs were randomized to either IMN or 0.045 in K-wire fixation after receiving a standardized neck osteotomy. Proper implant placement was confirmed with plain radiographs. Specimens then underwent loading in a 3-point bend configuration. Load to failure (LTF), stiffness, and fracture displacement were recorded. Mechanical failure was defined by a sharp change in the load-displacement curve.

RESULTS

Age, sex, sidedness (left or right), and digit (ring or small finger) were evenly distributed between groups. The IMN had a significantly higher LTF than K-wires (546 N vs 154 N, P < .001). The K-wire fixation demonstrated plastic deformation between 75 and 150 N. Intramedullary nail stiffness was higher than that of K-wires (155.89 N/mm vs 59.28 N/mm, P < .001).

CONCLUSIONS

When surgical fixation is indicated for metacarpal neck and shaft fractures, the threaded IMN is biomechanically superior to crossed K-wires with the application of 3-point bend.

Incidence of Loss of Reduction After Open Reduction Internal Fixation of Metacarpal Shaft Fractures

BACKGROUND

This study compared the incidence of loss of reduction (LOR) between metacarpal fractures fixed with screws alone and those fixed with plates and screws. Secondary aims included identifying patient or fracture characteristics associated with increased risk of LOR.

METHODS

We retrospectively reviewed 138 metacarpal fractures in 106 patients treated with open reduction internal fixation with screws (60 fractures) or plates and screws (78 fractures) with a mean radiographic follow-up of 50 days for evidence of LOR. We compared the incidence of LOR between the screw and plate groups using a χ2 test. We performed logistic regression analysis to determine whether patient age, sex, metacarpal location (index, long, ring, small), the presence of multiple metacarpal fractures, or fracture pattern were associated with increased incidence of LOR.

RESULTS

Loss of reduction occurred in 19 (13.8%) of 138 fractures, with no statistically significant difference between lag screw (7 of 60, 11.6%) and plate fixation (12 of 78, 15.4%). Neither fracture pattern nor the presence of multiple metacarpal fractures was associated with an increased incidence of LOR, but patients experienced a 7% increase in the risk of LOR for each additional year of age. Loss of reduction occurred most frequently in index metacarpal fractures (4 of 12, 33%), although this did not reach statistical significance.

CONCLUSIONS

We found no difference in LOR incidence between lag screw fixation and plate fixation. The overall incidence of LOR was higher in this study than previously reported and increased with increasing patient age.

Retrograde Intramedullary Screw Fixation for Metacarpal Fractures: A Systematic Review

Common forms of fixation of metacarpal fractures have historically included percutaneous Kirschner wire fixation, plates and screws, and, more recently, intramedullary screw fixation. Retrograde intramedullary screws (RISs) are a novel modality first described 10 years ago. The purpose of this review is to critically evaluate the published literature assessing outcomes of RIS fixation for metacarpal fractures and create a complication profile for this novel technique. A comprehensive literature search was performed using electronic databases for both clinical and biomechanical studies in relation to RIS fixation published from 2000 to 2020. A total of 19 studies (13 clinical and 6 biomechanical) met the inclusion criteria. The clinical studies examined 603 metacarpal fractures and demonstrated adequate functional outcomes in terms of grip strength, total active motion, and time to return to work. The biomechanical studies examined 80 metacarpal fractures, finding that load to failure in RISs was often equal to or higher than Kirschner wires but less than plate and screws. The complication rate in reviewed studies was 2.8%, with the most prevalent complications being stiffness and extension lag. RIS use in metacarpal fractures appears to provide adequate stability with satisfactory clinical outcomes and minimal complications, although more high-quality studies are needed to fully examine this modality.

Kickstand Technique for Intraoperative Reduction of Fifth Metacarpal Neck Fractures

This article reports a novel intraoperative technique for the reduction of angulated metacarpal neck fractures undergoing retrograde headless intramedullary screw fixation. This technique is a useful reduction maneuver, especially for hand surgeons operating without a first assistant, because it eliminates the need to hold manual reduction during implant placement.

[Osteosynthesis by intramedullary headless screw in digital fractures: A retrospective scannographic and anatomical study]

INTRODUCTION

Long finger skeletal fractures are common injuries. In displaced forms, surgical treatment is required. With the advent of headless cannulated screws, the technique has been simplified and allows reduction in both planes. The objective of our study was to evaluate the functional recovery of patients operated on by this technique.

MATERIAL AND METHOD

We conducted a retrospective single-center study between 2019 and 2022. Eleven patients were followed and 12 fractures analyzed. A radio-clinical follow-up was carried out at 1 month then at the last follow-up with an evaluation of the articular amplitudes and a quality of life score (QuickDash, QD). The time to return to professional and sporting activities, pain (EVA) was collected. An anatomical/scannographic evaluation was performed to assess tendon and cartilage damage.

RESULTS

At the last follow-up, the average global flexion was 266° and the extension was total. An average QD score of 15.9 and a Jamar force of 106% compared to the healthy side were observed. The return to physical and professional activities was earlier and the pain quickly tolerable. No secondary displacement was objectified and all were consolidated at the last follow-up, without malunion. No patient had been operated on secondarily.

CONCLUSION

This technique seems to be a safe and non-traumatic. It allows a faster return to sports and professional activities with fewer complications and no need to remove the material.

Intramedullary Compression Screw Fixation of Proximal Phalangeal Fractures: A Systematic Literature Review

Proximal phalangeal fractures have traditionally been fixed via either Kirschner wires or dorsal plating. Concerns regarding lack of compression and potential for infection with wire fixation, and adhesion formation and stiffness with plating, have lead to alternative fixation methods, such as intramedullary screw fixation. However, the literature regarding this modality is limited. Methods: A systematic review was performed to review the literature regarding intramedullary screw fixation for proximal phalangeal fractures. English language studies that reported original data and commented on at least one postoperative measure of function were eligible for inclusion. 4 studies were eligible for inclusion, with a further 3 studies assessing proximal and middle phalanges analysed separately. Total active motion was greater than 240° in all proximal phalangeal studies; mean post-operative DASH was 3.62. 6% of patients sustained a major complication. Intramedullary screw fixation of proximal phalangeal fractures is safe, providing stable fixation to allow early motion.

Morphological Analysis of Metacarpal Shafts With Respect to Retrograde Intramedullary Headless Screw Fixation

Background: The use of retrograde intramedullary headless compression screw fixation for metacarpal neck and shaft fractures has been described in the literature. The purpose of this study was to perform a computed tomography (CT)-based morphological analysis of metacarpal size to help surgeons anticipate expected hardware needs. Methods: In all, 108 consecutive hand CT scans were evaluated for the medullary diameter in the volar-dorsal and radial-ulnar planes at the narrowest point of the canal, as well as for the distance from the articular surface to this point. Results were then analyzed by finger and by sex. Results: The ring finger had the smallest average medullary canal diameter for both men and women (2.7 and 2.6 mm, respectively); the small finger had the largest average diameter (3.9 mm) for men and the middle finger (3.6 mm) for women. Radial-ulnar was the rate-limiting dimension in the index, middle, and ring fingers, whereas volar-dorsal was the smallest dimension in the small finger, regardless of sex. Medullary diameter tended to be larger in patients aged more than 50 years. More than 50% of fingers have diameters >3.0 mm, and at least 40% of index, middle, and small fingers have diameters >3.5 mm, which are common diameters of commercially available headless compression screws. Conclusions: When preparing to perform open reduction internal fixation of a metacarpal using retrograde intramedullary headless compression screws, the surgeon needs to be prepared with screws of larger diameters to optimize fixation. Screws of larger diameters are needed to achieve endosteal purchase, regardless of sex.

Headless Compression Screw for Metacarpal Nonunion: Description of a New Technique and Report of 4 Cases

Nonunion is a rare complication of metacarpal fractures and is usually associated with compound, open fractures with tissue loss and infection, or after failed surgical treatment. Repair by rigid osteosynthesis with plate and screws combined with autologous bone grafting has always been the treatment of choice for most patients. Such method allows early motion, although it has been proven that the presence of hardware may cause local soft tissue irritation. Often, hardware removal and tendon releases are necessary. We describe an original technique with a fixation method for the treatment of metacarpal nonunions, considering the excellent results attained with an intramedullary, headless screw for metacarpal fracture fixation. We report a series of three cases that evolved to bone healing with excellent clinical, functional, and radiographic outcomes.

Intramedullary Headless Screw Fixation of Metacarpal Fractures: A Radiographic Analysis for Optimal Screw Choice

Background: The purpose of this study was to investigate variations in radiographic metacarpal anatomy as it relates to intramedullary (IM) fixation of metacarpal fractures and to compare this anatomy with available headless screw dimensions. Methods: We radiographically analyzed posteroanterior and lateral (LAT) radiographs of 120 metacarpals across 30 patients without structural abnormalities. Primary outcomes included IM isthmus diameter, isthmus location, metacarpal cascade, and head entry point collinear with IM canal. Measurements were compared with a list of commercially available headless screws used for IM fixation. Results: The average largest isthmus diameter was in the small metacarpal (3.4 mm), followed by the index (2.8 mm), long (2.7 mm), and ring (2.7 mm) metacarpals. The average cascade angle between long and index, long and ring, and long and small metacarpals was 0°, 24°, and 27°, respectively. The appropriate head entry point ranged between 25% and 35% from the dorsal surface of the metacarpal head on a LAT view. The retrograde isthmus location of the index and long finger was 39.2 and 38.1 mm, respectively. Twenty-five screws from 7 manufacturers were analyzed with sizes ranging from 1.7 to 4.5 mm. Only 8 of 17 screws between 2.3 and 3.5 mm had a length range above 35 mm. Conclusions: Metacarpal head entry point and cascade angle can help identify the appropriate reduction with the guide pin starting point in the dorsal 25% to 35% of the metacarpal head. Surgeons should be mindful to choose the appropriate fixation system in light of the variations between metacarpal isthmus size, isthmus location, and available screw lengths.

Headless Compression Screw Fixation for Proximal Phalanx Fractures: A Biomechanical Study

Background: Proximal phalanx fractures are common injuries of the hand with multiple treatment options. Intramedullary (IM) screw fixation has become more widely used, and early outcomes are promising. However, biomechanical data regarding this type of fixation are sparse. Methods: Two methods of IM screw fixation of proximal phalanx fractures were tested in cadaver specimens. All specimens were treated with a single antegrade headless compression screw, with half getting the addition of a blocking screw. To test the most common deforming force of flexion-extension, each phalanx was subjected to apex volar 3-point bending using the Materials Testing System test frame. Results: There was no significant difference in the stiffness of 3-point bending with single antegrade screws alone and with a blocking screw (mean, 63.1 vs 52.2 N/mm; P = .27). When comparing smaller with larger specimens, stiffness of the small group was significantly greater than that of the large group when both fixation methods were included (85.3 vs 30.1 N/mm; P < .0002). When comparing stiffness with percent fill of the screw within bone, there was a moderately positive correlation (0.51). Conclusions: Addition of a blocking screw did not increase the stability of the IM screw fixation construct for proximal phalanx fractures. When comparing specimen size, the smaller bones were stiffer under 3-point bending load, regardless of the type of fixation. In addition, those specimens that had a larger longitudinal screw length to bone length ratio were stiffer. These findings provide valuable information as techniques for IM screw fixation of proximal phalanx fractures continue to evolve.

Biomechanical comparison of intramedullary screw fixation, dorsal plating and K-wire fixation for stable metacarpal shaft fractures

We compared four methods of metacarpal shaft fixation: 2.2 mm intramedullary headless compression screw; 3.0 mm intramedullary headless compression screw; intramedullary K-wire fixation; and dorsal plate fixation. Transverse mid-diaphyseal fractures were created in 64 metacarpal sawbones and were assigned into four groups. Peak load to failure and stiffness were measured in cantilever bending and torsion. We found that dorsal plating had the highest peak load to failure. However, initial bending stiffness of the 3.0 mm intramedullary headless compression screw was higher than that of the dorsal plates. In torsion testing, dorsal plating had the highest peak torque, but there was no significant difference in torsional stiffness between the plate and intramedullary headless compression screw constructs. We concluded that intramedullary headless compression screw fixation is biomechanically superior to K-wires in cantilever bending and torsion; however, it is less stable than dorsal plating. In our study, the initial stability provided by K-wire fixation was sufficient to cope with expected loads in the early rehabilitation period, whereas dorsal plates and IHCS constructs provided stability far in excess of what is required.

A Fourteen-year Review of Practice Patterns and Evidence-based Medicine in Operative Metacarpal Fracture Repair

The American Board of Plastic Surgery has been collecting practice data on metacarpal fracture operative repair since 2006 as part of its Continuous Certification process. These data allow plastic surgeons to compare their surgical experience to national trends. Additionally, these data present the opportunity to analyze those trends in relation to evidence-based medicine.

Intramedullary Fixation with Headless Screws versus Bouquet in Unstable Metacarpal Neck Fractures in Active Patients: A Randomized Study

Objeticve  To compare the range of motion (ROM), return-to-work time, visual analogue score (VAS), disability of the arm, shoulder, and hand (QuickDASH), and radiographic outcomes of two methods of definitive internal fixation in active patients with boxer's fractures, operated in the first week.

Methods  This was a prospective, randomized trial, in which 50 patients, with a mean age range of 18 to 40 years old, were randomized and treated to definitive intramedullary fixation using 2 headless screws ( n  = 20) or bouquet (2 or 3 Kirschner wires) ( n  = 20). The patients were assessed on return-to-work time, ROM, patient reported QuickDASH outcome, VAS, and radiographic evaluation at 6 months.

Results  At 6 months, there were no differences between the two groups in terms of ROM, postoperative pain (VAS), or QuickDASH score. The overall complication rate was 4.76% in the screw group, compared with 5% in the bouquet-fixation group.

Conclusions  In the treatment of the active patients with unstable boxer's fractures, headless screws and bouquet fixation proved to be a safe and reliable treatment. The outcomes were similar in both groups.

Analysis of 3 Different Operative Techniques for Extra-articular Fractures of the Phalanges and Metacarpals

Background: Several techniques have been described for treating metacarpal and phalangeal fractures. We sought to compare the 3 techniques most frequently used for extra-articular metacarpal and phalangeal fractures: plate screw (PS), Kirschner wire (KW), and retrograde intramedullary screw (RIS) fixation. We aimed to determine whether using an RIS provides better clinical outcomes than using either a PS or a KW fixation. Methods: We conducted a retrospective review of patients who underwent surgical treatment of metacarpal and phalangeal fractures from January 2011 to December 2017 in our department. Only patients with an acutely displaced short oblique or transverse extra-articular metacarpal or phalangeal fracture were included. Patients were classified into 3 groups depending on the treatment they received: PS, KW, or RIS fixation. The duration of each procedure was recorded. Clinical assessments included measuring total active motion (TAM), grip strength, and an evaluation of plain radiographs through to ultimate healing. A Disabilities of the Arm, Shoulder and Hand (QuickDASH) score was collected on all patients. Data were analyzed by analysis of variance or Kruskal-Wallis rank test, as indicated. Results: A total of 253 fractures (202 metacarpal and 51 phalangeal) in 230 patients were included in analysis. In all, 135 fractures (53.3%) underwent PS fixation; 53 (20.9%), KW fixation; and 65 (25.6%), RIS fixation. In the KW fixation group, Bouquet pinning was performed for metacarpal fractures and cross pinning for phalangeal fractures. When more than 1 fracture coexisted in the same patient, they were considered separate instances. No differences among the 3 groups were observed when evaluating mean time to radiological union, grip strength, TAM, or QuickDASH score. Mean surgery time was significantly shorter with KW (20 minutes) and RIS (25 minutes), than with PS (32 minutes). Mean return to work or routine activities time was significantly less in the RIS (7.8 weeks) group than in the PS and KW groups (8.3 and 9.2 weeks, respectively). Conclusions: Surgical treatment is recommended in patients with unstable metacarpal and phalangeal fractures. The use of RIS was associated with shorter mean surgery duration and return to work times than PS and KW, respectively.

How to Manage Complications Related to the Use of Intramedullary Screws in Metacarpal Fractures: Case Series

The use of intramedullary screws has been increasing among hand surgeons in cases of metacarpal fractures due to their low morbidity, and because they minimize incisions and dissection, and require less tissue manipulation and deperiostization. However, there are few published articles on the complications that arise from its use. Therefore, the purpose of the current study is to present a series of cases of complications following the use of intramedullary screws in metacarpal fractures that required surgical intervention, and to describe the surgical technique used to solve them .

Methods We performed a retrospective multicenter study in which we reviewed the clinical history, surgical descriptions and radiographs of the patients submitted to fixation of intramedullary compression screws for metacarpal fractures. We defined as complications infection, lesion to the extensor apparatus, bending of the implant, loss of reduction, hardware failure, malrotation, and non-union.

Results Out of a total of 45 patients, we reported 3 cases of complication: 1 patient with loss of reduction, and 2 patients with bending of the implant. In the three cases, the screw was removed without complications, and the focus of the fracture was stabilized.

Conclusion Intramedullary fixation with compression screws is increasingly being used for metacarpal fractures, with reports of low rates of complications. In the series of cases herein reported, the complications were solved without difficulty, and the patients showed a good recovery in hand function in the follow-up. Knowledge of the possible complications and their management enables us to provide more safety to the patient at the time of choosing this technique.

Comparison of clinical and radiological results of fixation methods with retrograde intramedullary Kirschner wire and plate-screw in extra-articular metacarpal fractures

OBJECTIVES

In this study, we aimed to compare clinical and radiographic outcomes of retrograde intramedullary Kirschner-wire (K-wire) fixation with those of plate-screw (PS) fixation.

PATIENTS AND METHODS

A total of 98 metacarpal shaft fractures in 75 patients (65 males, 10 females; mean age: 31.2±10.9 years; range, 16 to 65 years) were included between January 2011 and December 2017. The total joint active range of motion (AROM) and grip strength of the healthy and broken hands were evaluated. The Visual Analog Scale (VAS) and Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) scores were recorded. We compared surgery duration, number of fluoroscopy images, and cost-effectiveness for each technique.

RESULTS

The overall mean follow-up was 21.9 (range, 12 to 56) months. At the last follow-up, total joint AROM (p=0.072), VAS score (p=0.298), QuickDASH score (p=0.132), and hand grip strength (p=0.947) were similar between the groups. Radiological union occurred in the PS and K-wire groups in a mean of 5.84 (range, 3 to 8) and 4.46 (range, 3 to 20) weeks, respectively (p=0.173). A significant difference was found in surgery duration (p=0.021) and number of fluoroscopy images (p<0.05) between the PS and K-wire groups. Two wound complications were observed in the PS group and one with K-wires.

CONCLUSION

Retrograde intramedullary K-wire fixation has certain advantages such as being less invasive and more accessible with shorter operation time, compared to PS fixation. Similar radiological and clinical scores can be obtained in patients undergoing retrograde intramedullary K-wire fixation or PS fixation.

Intramedullary Metacarpal Screw Fracture Fixation: A Retrospective Review of the Rehabilitation Literature and an Illustrative Case Report With a Postoperative Therapy Protocol

ABSTRACT

Intramedullary metacarpal screw fixation has shown promising results and quick functional recovery with the proper postoperative rehabilitation. The rehabilitative process after this procedure has not been compared across literature. A retrospective review of literature was used to recommend a therapy timeline, activity and recommendations to allow for proper postoperative rehabilitation for optimal results. An illustrative case report is presented to explain technique and outcomes.

Intramedullary percutaneous fixation of metacarpal fractures: screw versus connected K-wires

The purpose of the present study was to determine clinical and radiographic outcomes in patients treated with limited-open retrograde intramedullary headless screw fixation for metacarpal neck and shaft fractures (group I) versus percutaneous antegrade and retrograde intramedullary double pinning linked by a connector (group II). We designed a retrospective comparative study, with the inclusion of two groups (20 patients each) of metacarpal unstable fractures. Both groups showed similar outcomes at the final follow-up, except for extension lag (significantly better in group II) and return to sport (significantly better in group I). Intramedullary screw fixation did not accelerate bone union and range of motion recovery in the early follow-up. In conclusion, limited-open retrograde intramedullary headless screw fixation and percutaneous connected antegrade and retrograde intramedullary double pinning are both reliable techniques of fixation for metacarpal neck and shaft fractures. LEVEL OF EVIDENCE: III.

Evaluation of Antegrade Intramedullary Compression Screw Fixation of Metacarpal Shaft Fractures in a Cadaver Model

PURPOSE

Surgical options for displaced metacarpal shaft fractures include the use of Kirschner wires, plates and screws, and most recently, intramedullary headless compression screws (IMHCS), which have been reported using only retrograde insertion through the metacarpal head. We evaluated IMHCS fixation of metacarpal shaft fractures through an antegrade approach in a cadaver model.

METHODS

We performed antegrade placement of IMHCS in 10 cadaver hands including all 5 digits (total of 50). Displaced transverse proximal metacarpal shaft fractures were created and reduced with a retrograde guidewire from the metacarpal head across the shaft fracture and exiting the metacarpal base. This was retrieved through a 6-mm dorsal wrist incision and overdrilled before the placement of a 4.1-mm-diameter IMHCS in the ring finger and a 4.7-mm screw in all other metacarpals. After IMHCS placement, carpometacarpal (CMC) joint violation was measured along with the optimal starting point for the guidewire on the metacarpal head relative to the dorsal cortex.

RESULTS

In all 50 metacarpals, we achieved successful fracture reduction and fixation without violating the extensor mechanism at the wrist. Our retrograde guidewire entry point through the metacarpal head ranged from 4.2 to 4.7 mm volar to the dorsal cortex. The actual area of CMC joint violated by IMHCS placement was largest in the index CMC joint (4.9%), followed by the middle (3.7%), little (2.9%), ring (0.5%), and thumb joints (0.2%).

CONCLUSIONS

Placement of IMHCS through an antegrade approach from the CMC joint can be performed effectively for all transverse metacarpal fractures, including the thumb, using a limited incision. There is minimal violation of the articular surfaces of the trapezium, capitate, and hamate for the thumb, middle, ring, and little metacarpals.

CLINICAL RELEVANCE

Antegrade IMHCS fixation successfully avoids the potential morbidity of creating a metacarpal head articular surface or extensor mechanism defect at the metacarpophalangeal joint seen with the retrograde approaches.

Intramedullary screw fixation of metacarpal and phalangeal fractures - A systematic review of 837 patients

Intramedullary screw (IMS) fixation is increasingly used as an alternative treatment option in metacarpal and phalangeal fractures of the hand. However, this technique is currently the subject of controversy among hand surgeons. The aim of this systematic review was to gain insight on radiological, functional and patient-rated outcomes reported in literature. A comprehensive literature search of PubMed, Embase, CENTRAL and CINAHL databases was conducted on March 1st, 2021. All studies reporting on fracture union, complications, and functional and patient-rated outcome in IMS fixation of metacarpal and/or phalangeal fractures were selected. Two prospective and 16 retrospective cohort studies were included, encompassing a total of 837 patients with 958 fractures (693 metacarpal, 222 proximal phalangeal and 43 middle phalangeal). Mean surgery duration was 26.4 min (range 5-60 min). Union was ultimately achieved in all fractures in a mean of 5.7 weeks (range 2-12 weeks). The procedure-related complication rate was 3.2%. The most frequently reported complication was limitation of joint motion, occurring in 2.0% of cases. Incidence of other complications, including loss of reduction, infection and screw protrusion did not exceed 1%. Overall mean total active motion averaged 243° and grip strength reached 97.5% of the contralateral side. The Disabilities of the Arm, Shoulder and Hand (DASH) score averaged 3.7 points. Duration of sick leave was 7.3 weeks. According to the findings of this systematic review, IMS fixation is a time-saving and safe minimally invasive solution for both metacarpal and phalangeal fractures, with a low rate of complications and promising functional and patient-rated results.

Metacarpal shaft fixation: a biomechanical comparison of dorsal plating, lag screws, and headless compression screws

Background

Metacarpal shaft fractures are common and can be treated nonoperatively. Shortening, angulation, and rotational deformity are indications for surgical treatment. Various forms of treatment with advantages and disadvantages have been documented. The purpose of the study was to determine the stability of fracture fixation with intramedullary headless compression screws in two types of metacarpal shaft fractures and compare them to other common forms of rigid fixation: dorsal plating and lag screw fixation. It was hypothesized that headless compression screws would demonstrate a biomechanical stronger construct.

Methods

Five matched paired hands (age 60.9 ± 4.6 years), utilizing non-thumb metacarpals, were used for comparative fixation in two fracture types created by an osteotomy. In transverse diaphyseal fractures, fixation by headless compression screws (n = 7) and plating (n = 8) were compared. In long oblique diaphyseal fractures, headless compression screws (n = 8) were compared with plating (n = 8) and lag screws (n = 7). Testing was performed using an MTS frame producing an apex dorsal, three point bending force. Peak load to failure and stiffness were calculated from the load-displacement curve generated.

Results

For transverse fractures, headless compression screws had a significantly higher stiffness and peak load to failure, means 249.4 N/mm and 584.8 N, than plates, means 129.02 N/mm and 303.9 N (both p < 0.001). For long oblique fractures, stiffness and peak load to failure for headless compression screws were means 209 N/mm and 758.4 N, for plates 258.7 N/mm and 518.5 N, and for lag screws 172.18 N/mm and 234.11 N. There was significance in peak load to failure for headless compression screws vs plates (p = 0.023), headless compression screws vs lag screws (p < 0.001), and plates vs lag screws (p = 0.009). There was no significant difference in stiffness between groups.

Conclusion

Intramedullary fixation of diaphyseal metacarpal fractures with a headless compression screw provides excellent biomechanical stability. Coupled with lower risks for adverse effects, headless compression screws may be a preferable option for those requiring rapid return to sport or work.

Level of evidence

Basic Science Study, Biomechanics.

Osteosynthesis of Fractures of the Metacarpal Neck with Self-Compressing Screw - Preliminary Analysis of 21 Cases

Objective  The present study aims to analyze the clinical results of the surgical treatment of metacarpal neck fractures with retrograde intramedullary fixation using cannulated headless screws (Herbert type).

Methods  Retrospective study of 21 closed fractures deviated from the metacarpal neck in 21 patients operated between April 2015 and November 2018.

Results  The sample included 19 men and 2 women. The mechanisms that caused the trauma were punching, falling to the ground and motor vehicle accident (n = 14, 5 and 2). The affected metacarpals were the 5 ^th , 3 ^rd , and 2 ^nd (n = 19, 1 and 1). Surgical indications were neck-shaft diaphysis of the metacarpal > 30° for the 2 ^nd and 3 ^rd metacarpals and > 40° for the 5 ^th metacarpal, shortening ≥ 5mm, rotational deviation, and the desire of the patient not to use plaster cast. In the immediate postoperative period, patients remained without immobilization and were instructed to mobilize their fingers according to tolerance. All patients had total active mobility > 240° and returned to their former occupations. All fractures consolidated and there were no reinterventions.

Discussion  The great advantages of the headless screw technique are its low morbidity, sufficient stability to avoid external immobilization, and reproducibility at low cost.

Conclusion  This is an easy, fast technique that has excellent results for the surgical treatment of displaced fractures of the neck of the metacarpals.

An Anatomical Study of Metacarpal Morphology Utilizing CT Scans: Evaluating Parameters for Antegrade Intramedullary Compression Screw Fixation of Metacarpal Fractures

PURPOSE

This study evaluated metacarpal morphology for antegrade placement of intramedullary headless compression screws (IMHCS) for metacarpal fracture fixation.

METHODS

We analyzed 100 hand computed tomography scans to quantify cortical thickness, intramedullary diameter, and metacarpal lengths. In addition, dorsal or ulnar overhang of the metacarpals over their respective carpal bones was measured. We also predicted optimal entry points for guidewire placement at the metacarpal head.

RESULTS

The ring finger metacarpal had the narrowest medullary canal width (coronal, 2.8 mm; sagittal, 3.5 mm). Not counting the thumb, the little finger metacarpal had the widest midshaft medullary width of 4.1 mm in the coronal plane and the middle metacarpal was widest in the sagittal plane with canal width of 3.9 mm. On average, there was maximal dorsal overhang at the base of the middle metacarpal (4.2 mm) and maximal ulnar overhang at the base of the small metacarpal (3.9 mm). The optimal entry point for guidewire placement over each metacarpal head was approximately 3.5 to 3.8 mm volar to the dorsal cortex.

CONCLUSIONS

Minimum IMHCS diameters of 3.5 mm for the ring and 4.0 mm for the index, middle and little fingers are necessary to achieve interference fit within the medullary canal. Minimum screw lengths of 38 mm would be needed to ensure 6 mm fixation past the midshaft of the metacarpals. Antegrade IMHCS for fixation of proximal metacarpal fractures may be most feasible with thumb, middle, and little finger metacarpals because there was larger dorsal or ulnar overhang to allow screw placement without violating the carpometacarpal joints.

CLINICAL RELEVANCE

Our analysis provides a reference guide for intramedullary screw sizes for each metacarpal of the hand to achieve interference fit with fracture fixation. Furthermore, the dorsal and ulnar overhangs of the metacarpal bases suggest the practicality of antegrade IMHCS fixation.

Single versus dual elastic nails for closed reduction and antegrade intramedullary nailing of displaced fifth metacarpal neck fractures

Closed reduction and internal fixation with antegrade intramedullary nails is a feasible and effective treatment for displaced fifth metacarpal neck fractures (FMNFs). The present study aimed to compare clinical and radiological outcomes in patients with displaced FMNFs after treatment with single or dual antegrade elastic intramedullary nails (AEIMNs). Thirty-three patients were treated with a single 2.0 mm AEIMN and 34 patients were treated with two 1.5 mm AEIMNs. Clinical and radiological outcomes included grip strength, active range of motion (ROM), active flexion and extension of the fifth metacarpophalangeal (MCP) joint, dorsal angulation loss, and metacarpal shortening of the fifth metacarpal at 12 months after treatment. No significant difference was observed between the two groups with respect to grip strength, ROM or flexion of the fifth MCP joint. The average values of dorsal angulation loss, metacarpal shortening, and extension of the fifth MCP joint of the dual nails group were better than those of the single nail group (dorsal angulation loss, 2.79 ± 1.93° vs. 4.05 ± 1.59°, P = 0.009; metacarpal shortening, 1.66 ± 0.80 mm vs. 2.12 ± 0.88 mm, P = 0.028; extension of the fifth MCP joint, 7.71 ± 4.43° vs. 4.82 ± 4.09°, P = 0.012). In conclusion, dual AEIMNs fixation provided better MCP extension and radiological outcomes than single AEIMN fixation.

Intramedullary compression screw fixation of metacarpal and phalangeal fractures

The intramedullary headless compression screw (IMCS) technique represents a reliable alternative to percutaneous Kirschner-wire and plate fixation with minimal complications.

Transverse fractures of the metacarpal shaft represent a good indication for this technique. Non-comminuted subcapital and short oblique fractures can also be treated with IMCS.

This technique should not be used in the presence of an open epiphysis, infection and, most of all, in subchondral fractures, because of the lack of purchase for the head of the screw.

A double screw construct is recommended for comminuted subcapital fractures of the metacarpal to avoid metacarpal shortening. IMCS can even be applied for peri-articular fractures of the proximal third of the phalanx and in some multi-fragmentary proximal and middle phalangeal fractures.

Usually the intramedullary screws are not removed. The main indications for screw removal are joint protrusion, infection and screw breakage after new fracture.

Cite this article: EFORT Open Rev 2020;5:624-629. DOI: 10.1302/2058-5241.5.190068

Clinical Outcomes of Limited Open Intramedullary Headless Screw Fixation of Metacarpal Fractures in 91 Consecutive Patients

Background: The objective of the study is to evaluate clinical and radiographic outcomes in patients treated with limited-open retrograde intramedullary headless screw (IMHS) fixation for metacarpal neck and shaft fractures. Methods: Retrospective review of 91 consecutive patients (79 men; 12 women), mean age 28 (range =15-69) years, treated with IMHS fixation for acute displaced metacarpal neck (N = 56) and shaft (N = 35) fractures at a single institution. Mean follow-up was 10 (range = 1-71, median = 3) months. Preoperative mean magnitude of metacarpal neck angulation was 48° (range = 0°-90°), and mean shaft angulation was 42° (range = 0°-70°). Active motion was initiated within 5 days postoperatively. Clinical outcomes were assessed with digital goniometry, grip strength, and return to full activity. The time to radiographic union and radiographic arthrosis was assessed. Results: All 91 patients achieved full functional arc of metacarpophalangeal (MCP) motion, and all achieved full active MCP extension or hyperextension. At mean follow-up of 10 months, postoperative mean MCP joint flexion-extension arc was 88° (range = 55°-110°). Grip strength was available for 52 patients and measured 104.1% of the contralateral hand (range = 58%-230%). Radiographic union data were available for 86 patients. Seventy-six percent (65/86) achieved radiographic union by the end of week 6 (range = 2-10 weeks). Early arthrosis was noted in 1 patient at the MCP. There were 3 cases of shaft refracture after recurrent blunt trauma, following prior evidence of full osseous union. Conclusions: The IMHS fixation is safe, reliable, and durable for metacarpal neck/subcapital, axially stable shaft fractures, and select delayed unions or malunions. It allows for early postoperative motion without affecting union rates and obviates immobilization. This technique offers distinct advantages over formal open reduction and percutaneous Kirschner wire techniques.

Low Rate of Complications Following Intramedullary Headless Compression Screw Fixation of Metacarpal Fractures

Background: There has been a recent increase in the use of headless compression screws for fixation of metacarpal neck and shaft fractures as they offer several advantages, and minimal complications have been reported. This study aimed to evaluate the clinical complications and their solutions following retrograde intramedullary headless compression screw fixation of metacarpal fractures. We describe complications and the approach to their management. Methods: We performed a multicenter case series through retrospective review of all patients treated with intramedullary headless screw fixation of metacarpal fractures by 3 fellowship-trained hand surgeons. Patient demographics, implant used, type of complication, pre- and postoperative radiographs, operative reports, and sequelae were reviewed for each case. We defined complications as infection, loss of fixation, hardware failure, malrotation, nonunion, malunion, metal allergy, and any repeat surgical intervention. Results: Four complications (2.5%) were identified through the review of 160 total metacarpal fractures. One complication was a nickel allergy, one was a broken screw after repeat trauma, and 2 patients had bent intramedullary screws. Screw removal in 3 patients was simple and without complications or persistent limitations. One bent screw with a refracture was left in place. No serious complications were seen. Conclusion: Intramedullary screw fixation of metacarpal fractures is safe with a low incidence of complications (2.5%) that can be safely and effectively managed.

Clinical Outcomes of Ready-Made J-Shaped Nail Fixation for Unstable Metacarpal Fractures

Background: The purpose of this study was to report the clinical outcomes of ready-made J-shaped intramedullary nail fixation for unstable metacarpal fractures. Methods: A total of 25 unstable fractures from 24 patients were evaluated in this retrospective study, comprising 20 metacarpal neck and 5 metacarpal shaft fractures. The mean follow-up was 22 weeks. Functional outcomes were assessed based on the range of motion of the metacarpophalangeal joint. Radiographic outcomes were evaluated by four projections of the postoperative plain radiographs at the final follow-up, and then were rated as excellent if projections at the fracture site showed no correction loss or angular deformity greater than 10°. Surgery time and complications during the treatments were recorded for each case. Results: All 25 fractures obtained bony union. The mean range of motion of the metacarpophalangeal joint was 78° (range, 45°-90°). Radiographic outcomes were excellent in 24 (96%) of 25 fractures. Only one fracture had correction loss. The mean surgery time was 29 minutes (range, 14-61 minutes). Two cases had extensor tendon adhesion at the insertion site, which was easily released when the implant was removed. Conclusions: This study demonstrates that intramedullary fixation with a ready-made J-shaped nail is a reliable treatment option for unstable metacarpal fractures.

Intramedullary screw fixation for metacarpal shaft fractures: a biomechanical human cadaver study

Intramedullary cannulated compression screws have been introduced for the fixation of unstable metacarpal fractures. In the present study, this technique was compared with dorsal compression plating to evaluate its biomechanical performance in stabilizing metacarpal shaft fractures. In a first set of experiments, the biomechanical characteristics of the screws were analysed in an artificial bone model. In subsequent experiments, midshaft osteotomies were performed in human cadaver metacarpals, followed by plating or intramedullary screw osteosynthesis. The metacarpals were tested to failure in cantilever bending, following a stepwise increasing cyclic loading protocol. We found a significantly lower load at failure and a significantly lower number of cycles to failure in the intramedullary screw group, but both methods offered sufficient stability under these loads. With reference to published loads on the metacarpals during use of the hand, we conclude that intramedullary osteosynthesis yields sufficient strength and stiffness for early active motion. A difference in its fixation stability is noted compared with plate fixation, which may not be clinically relevant.

Retrograde intramedullary headless compression screws for treatment of extra-articular thumb metacarpal base fractures

The purpose of the study was to evaluate clinical and radiological outcomes of extra-articular fractures involving the base of the thumb metacarpal treated with fixation using a retrograde intramedullary cannulated headless screw. A review of prospectively collected data was conducted on a consecutive series of 13 patients, treated with headless screw fixation for acute displaced fractures. All workers resumed full duties, while non-workers returned to unlimited leisure activities within a mean of 42 days. At 3 months follow-up, all range of motion measurements in the treated and untreated thumb were similar. Mean visual analogue pain score was 0.8 at rest and 1.4 during exercise and mean Quick Disabilities of the Arm, Shoulder, and Hand score was 5. All patients achieved radiographic union by 8 weeks. We conclude that the intramedullary headless screw fixation is safe and reliable for base of thumb metacarpal fractures, allowing for early postoperative motion and good functional recovery. Level of evidence: IV.

Cartilage and extensor tendon defects after headless compression screw fixation of phalangeal and metacarpal fractures

Osteosynthesis of metacarpal and phalangeal fractures with headless compression screws leads to a defect in the articular surface and possibly damage to the extensor tendons. This study aimed to quantify the articular surface defect and extensor tendon injuries after implant placement in cadaveric hands. Defect size was assessed with computed tomography. Extensor tendon injuries were assessed by direct visualization and measurement after dissection. In the middle phalanx, the defect size in relation to the joint surface was significantly smaller after anterograde screw placement when compared with retrograde placement. Also, a mini-open approach was found to cause significantly less tendon injury than a percutaneous approach, but there was no difference in tendon damage between retrograde and antegrade screw insertion into the middle phalanx.

Intramedullary Headless Screw Fixation for Metacarpal Fractures

Multiple techniques have been proposed for metacarpal fracture fixation, including percutaneous Kirschner-wires, interfragmentary screws, plate and screw constructs, intramedullary (IM) nails, and cannulated IM headless screws. Each of these treatment options has its proposed advantages and disadvantages, and there remains no consensus on the optimal mode of treatment. We describe a technique of retrograde IM headless screw fixation for extra-articular metacarpal fractures.