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

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.

Determining the Optimal Intramedullary Screw Canal Fill Ratio in Length Unstable Metacarpal Fractures: A Biomechanical Investigation

PURPOSE

Intramedullary (IM) screw fixation is gaining popularity in the treatment of metacarpal fractures. Despite its rapid adoption, there is a paucity of evidence regarding parameters to optimize effectiveness. This study aimed to quantify the relationship between stability, IM screw size, and canal fill using a cadaveric model.

METHODS

Thirty cadaveric metacarpals (14 index, 13 middle, and three ring fingers; mean age: 58.3 years, range: 48-70) were selected to allow for canal fill ratios of 0.7-1.1 for screws sized 3.0, 3.5, and 4.5 mm. Metacarpals underwent a 45° volar-dorsal osteotomy at the midpoint before fixation with an IM screw. Specimens were subjected to 100 cycles of loading at 10 N, 20 N, and 30 N before load-to-failure testing. Correlation coefficients for angular displacement on the final cycle at each load, peak load to failure, and average stiffness were assessed.

RESULTS

Correlation coefficients for the angular displacement on the 100th cycle were as follows: 10 N, R = 0.62, 20 N, R = 0.57, and 30N, R = 0.58. Correlation values for peak load to failure as a function of canal fit were as follows: 3.0 mm, R = 0.5, 3.5 mm, R = 0.17, and 4.5 mm, R = 0.44. The canal fill ratio that intersected the line-of-best fit at an angular deformity of 10° was 0.74. Average peak forces for 3.0-, 3.5-, and 4.5-mm screws were 79.5, 136.5, and 179.6 N, respectively. Average stiffness for each caliber was 14.8, 33.4, and 52.3 N/mm.

CONCLUSIONS

Increasing screw diameter and IM fill resulted in more stable fixation, but marginal gains were seen in ratios >0.9. A minimum fill ratio of 0.74 was sufficient to withstand forces of early active motion with angular deformity <10°.

CLINICAL RELEVANCE

An understanding of the relationship of IM fill ratio of metacarpal screws to fracture stability may provide a framework for clinicians to optimally size these implants.

Dorsal Plating, Lateral Plating, and Intramedullary Screw Fixation of Extra-Articular Proximal Phalangeal Fractures: A Cadaveric Biomechanical Comparison

PURPOSE

To provide a biomechanical comparison of dorsal plating, lateral plating and intramedullary screw [IMS] fixation for extra-articular proximal phalangeal fractures.

METHODS

Midshaft osteotomies were performed on 36 cadaveric proximal phalanges. The phalanges were fixed by dorsal plating, lateral plating or IMS fixation, and subjected to a four-point bending force. Force was applied to achieve displacement of 1 mm/s, until construct failure or to a maximum of 10 mm of displacement. Clinical failure was defined as 2 mm of displacement, and force required to result in 1 mm and 2 mm of displacement was recorded, as was mode of failure.

RESULTS

Dorsal plating [127.5 N ± 52.6; 46.51-229.17] and lateral plating [77.1 N ± 25.1; 48.3-113.8] required significantly greater force to achieve 1 mm of displacement when compared to IMS [41.2 N ± 12.4; 20.6-62.3]. Dorsal plating [339.2 N ± 91.8; 158.5-538.6] required significantly greater force than lateral plating [154.5 N ± 33.8; 99.0 -204.4] and intramedullary screw fixation [110.0 ± 38.6; 51.1-189.3] to result in 2 mm of displacement. Lateral and dorsal plating constructs failed through plate bending, screw cut-out or plate failure, whilst IMS failed via implant deformity. All three constructs required greater force to result in even 1 mm of displacement than what is likely subjected through rehabilitation via active motion.

CONCLUSIONS

Lateral plating and IMS fixation offer sufficient stiffness to withstand the likely forces subjected via early active motion without displacement.

CLINICAL RELEVANCE

Dorsal plating required significantly greater force than lateral plating and intramedullary screw fixation to achieve 1 mm of displacement when used in extra-articular proximal phalangeal fractures in an in vitro setting. However, all three modalities confer enough stability to likely withstand the forces associated with active range of motion.

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.

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.

Metacarpal fractures

Metacarpal fractures are common and can be functionally disabling. The majority are managed non-operatively. When surgical intervention is indicated, various methods of fixation are available with the utility of each being based on injury pattern, patient function and surgeon preference. Early mobilization, especially in case of open reduction and internal fixation, is a critical component of treatment to prevent stiffness and restore function. When possible, a fixation construct that can withstand the applied forces of early postoperative motion is chosen. We provide an updated description for diagnosis, treatment options and operative fixation for metacarpal fractures.

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.

Cost Analysis of Intramedullary Screw versus Plate Osteosynthesis for Phalangeal and Metacarpal Fractures: An Observational Study

Background: To compare the observed healthcare and societal costs of intramedullary screw (IMS) and plate fixation of extra-articular metacarpal and phalangeal fractures in a contemporary Australian context. Methods: A retrospective analysis, based on previously published data, was performed utilising information from Australian public and private hospitals, the Medicare Benefits Schedule (MBS) and the Australian Bureau of Statistics. Results: Plate fixation demonstrated longer surgical lengths (32 minutes, compared to 25 minutes), greater hardware costs (AUD 1,088 vs. AUD 355), more extended follow-up requirements (6.3 months, compared to 5 months) and higher rates of subsequent hardware removal (24% compared to 4.6%), resulting in an increased healthcare expenditure of AUD 1,519.41 in the public system, and AUD 1,698.59 in the private sector. Wage losses were estimated at AUD 15,515.78 when the fracture cohort is fixed by a plate, and AUD 13,542.43 when using an IMS - a differential of AUD 1,973.35. Conclusions: There is a substantial saving to both the health system and the patient when using IMS fixation over dorsal plating for the fixation of extra-articular metacarpal and phalangeal fractures. Level of Evidence: Level III (Cost Utility).

Intramedullary Metacarpal Fracture Fixation: A Biomechanical Study of Screw Diameter and Comparison With Intramedullary Wire Stabilization

PURPOSE

Interest in intramedullary metacarpal fracture fixation (IMFF) with screws is increasing. However, the optimal screw diameter for fracture fixation is not yet established. In theory, larger screws should be more stable, but there is concern about long-term sequelae of larger metacarpal head defects and extensor mechanism injury created during insertion as well as implant cost. Therefore, the purpose of this study was to compare different diameter screws for IMFF to a popular and more cost-effective alternative of intramedullary wiring.

METHODS

Thirty-two cadaveric metacarpals were used in a transverse metacarpal shaft fracture model. Treatment groups consisted of IMFF with 3.0 × 60 mm, 3.5 x 60 mm, and 4.5 x 60 mm screws as well as 4 1.1-mm intramedullary wires. Cyclic cantilever bending was performed with the metacarpals mounted at 45° to simulate physiologic loading. Cyclical loading at 10, 20, and 30 N was performed to determine fracture displacement, stiffness, and ultimate force.

RESULTS

At 10, 20, and 30 N of cyclical loading, all screw diameters tested provided similar stability as measured by fracture displacement and were superior to the wire group. However, ultimate force under load to failure testing was similar between the 3.5- and 4.5-mm screws and superior to 3.0-mm screws and wires.

CONCLUSIONS

For IMFF, 3.0, 3.5, and 4.5-mm diameter screws provide adequate stability for early active motion and are superior to wires. When comparing the different screw diameters, 3.5- and 4.5-mm diameter screws offer similar construct stability and strength superior to the 3.0-mm diameter screw. Therefore, to minimize metacarpal head morbidity, smaller screw diameters may be preferable.

CLINICAL RELEVANCE

This study suggests that IMFF with screws is biomechanically superior to wires in cantilever bending strength in the transverse fracture model. However, smaller screws may be sufficient to permit early active motion while minimizing metacarpal head morbidity.

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.

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.

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.

Management of metacarpal fractures

The metacarpal fractures are common fractures which are treated by orthopaedic surgeons, plastic surgeons and hand surgeons equally. These are seen in young adults who have active life style. These have a major impact in life style of the patients if these are not treated adequately. The management of the fractures vary among surgeons to surgeons; two surgeons in the same centre can have a different treatment plan for a fracture. There are no standard guidelines for the treatment and it ranges from conservative management, Kirschner's wire (K-wires), plates and screws. This review article is about the management of metacarpal fractures where the commonly done procedures are reviewed.