Retrograde Intramedullary Screw Fixation for Metacarpal Fractures: A Systematic Review

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.

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.

Metacarpal Fracture Fixation with Intramedullary Screws

Background: Intramedullary screws (IMS) have become a viable option for metacarpal fracture fixation. To further appraise their utility, this study assessed clinical and patient-reported short- and medium-term outcomes of IMS fixation for extra-articular metacarpal fractures. Methods: A retrospective cohort study was performed in a series of 32 patients (with a total of 37 fractures) who underwent metacarpal fracture fixation over a 42-month period between January 2020 and July 2023. Results: Mean time for return to work was 39.8 days; mean time for return to full function was 88.4 days; total active motion was 250.7° (range: 204.9-270.9); Quick Disabilities of the Arm, Shoulder and Hand score was 2.3 (range: 0-22.7); mean visual analogue pain score was 0.9 out of 10 (range: 0-6) and a single complication was observed. Conclusions: The use of IMS in metacarpal fracture fixation is a practicable surgical option. IMS fixations yields a satisfactory duration for return to function, good postoperative range of movement, modest pain scores and low rates of complications. Level of Evidence: Level IV (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 Between Intramedullary Nail and Percutaneous Pin Fixation in Proximal Phalanx Fractures

BACKGROUND

Percutaneous pinning has been the predominant technique for fixation of proximal phalanx fractures, but stiffness is a reported complication. The introduction of intramedullary (IM) nail fixation of proximal phalanx fractures provides a stronger biomechanical fixation for amenable fracture patterns with the added benefit of not tethering the soft tissue. The goal of this study was to compare the surgical outcomes of IM nail and percutaneous pin fixation in isolated proximal phalanx fractures.

METHODS

A retrospective review was performed at our institution between the years 2018 and 2022 for patients treated for proximal phalanx fractures. Patients that underwent fixation with IM nails or percutaneous fixation for isolated extraarticular proximal phalanx fractures were included. Patients were excluded if they had concomitant hand fractures, tendon injury, or intraarticular extension.

RESULTS

A total of 50 patients were included in this study. Twenty-eight patients received percutaneous pin fixation, and 22 patients underwent IM nail or screw fixation. There was no significant difference in injury patterns or demographics between these two groups. Patients that underwent IM nail fixation had a significantly quicker return to active motion, shorter duration of orthosis treatment, and fewer occupational therapy visits. In addition, patients in the IM fixation group had significantly improved range of motion (ROM) at 6 weeks postoperatively.

CONCLUSIONS

This study demonstrates that patients receiving percutaneous pin or IM nail fixation have equivocal union and complication rates. The IM nail fixation group was able to have quicker return to mobilization, fewer required occupational therapy visits, and improved early ROM.

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.

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.

Antegrade Intramedullary Screws in Metacarpal Fractures of Pediatric Patients

Metacarpal fractures are common injuries in pediatric patients. In adults, cannulated intramedullary screws are an excellent stabilization option for metacarpal fractures and are widely used, but in pediatric patients with open physes, their use is a relative contraindication. The risk of injury to the physis in classic retrograde screw placement makes this type of osteosynthesis not an option. We present the case of an 8-year-old patient with fractures of two adjacent metacarpals with rotational malalignment and scissoring, in which closed reduction was performed, and stabilization with cannulated intramedullary screws using antegrade placement to avoid injury to the physis.

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.

Fixation of Hand Fractures with Intramedullary Headless Compression Screws

Metacarpal and phalangeal fractures remain among the most frequently encountered orthopedic injuries, accounting for 10% of all fractures. For operative fractures, there is an array of treatment options with percutaneous kirschner wire stabilization and screw and plate fixation strategies predominating. Recently, a new fixation method was introduced, intramedullary (IM) fixation with headless screws, which has advantages of a percutaneous technique and buried hardware. The purpose of this review is to highlight the indications and surgical techniques of IM screw fixation of metacarpal and phalangeal fractures. Although more research is needed, IM fixation represents a potentially reliable alternative to Kirschner-wire and plate fixation.

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.