Drill Penetration Injury to Extensor Tendons: A Biomechanical Analysis

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.

Extensor Tendon Integrity After Percutaneous Placement of Intramedullary Metacarpal Screws: A Cadaveric Study

BACKGROUND

Intramedullary implants are an increasingly common method for fixation of metacarpal fractures. Numerous techniques for instrumentation have been described with varied consideration for the risk of extensor tendon injury. The current cadaveric study evaluates the prevalence and degree of extensor tendon injury and compares percutaneous approaches with different drilling techniques.

METHODS

Ninety-six metacarpals (thumbs excluded) from 24 fresh-frozen cadaveric upper extremities were used to compare 2 percutaneous approaches and 2 drilling techniques. This resulted in 4 subgroups available for comparison: oscillate to bone (OB), forward to bone (FB), oscillating through the skin (OS), and forward through the skin (FS). After instrumentation, the extensor tendons were dissected and disruption was characterized. The main outcome measures were tendon "hit rate" and relative extensor tendon defect width.

RESULTS

Tendon hit rate was significantly higher in the long finger (LF), that is, 79.2%, compared with other metacarpals: index finger, 20.8%; ring finger, 12.5%; and small finger 25%. The mean relative tendon disruption was significantly less in the OB group (16.05%) compared with the other groups: FB (31.84%), FS (31.50%), and OS (29.85%).

CONCLUSION

Retrograde intramedullary screw fixation of metacarpal fractures can be performed using percutaneous approaches without a significant disruption of the extensor mechanism. Instrumentation through a longitudinal stab incision down to the metacarpal head and the use of drill oscillation minimize injury to the extensor tendons. The LF extensor tendon is most at risk with retrograde intramedullary implant placement.

Power-Tool Use in Orthopaedic Surgery: Iatrogenic Injury, Its Detection, and Technological Advances: A Systematic Review

Power tools are an integral part of orthopaedic surgery but have the capacity to cause iatrogenic injury. With this systematic review, we aimed to investigate the prevalence of iatrogenic injury due to the use of power tools in orthopaedic surgery and to discuss the current methods that can be used to reduce injury.

Intramedullary Screw Fixation Comprehensive Technique Guide for Metacarpal and Phalanx Fractures: Pearls and Pitfalls

Background:

Phalangeal and metacarpal fractures are the second and third most common upper extremity fractures after distal radius fractures with varying methods of fixation techniques. Intramedullary screw fixation is an increasingly preferred method of fixation. Benefits include early range of motion, faster recovery, limited dissection, and reduced complications. Improper technique, which is readily avoidable, can lead to suboptimal results.

Methods:

A review of recent literature on current techniques aims to summarize the biomechanics of intramedullary screw fixation and outline appropriate technique of placing headless compression screws for metacarpal and phalangeal fractures.

Results:

We discuss through images and videos the indications, preoperative workup, and technical pearls and pitfalls to encourage surgeons to add this technique to their armamentarium and improve outcomes.

Conclusions:

intrameduallry screw fixation is a powerful option for metacarpal and phalanx fixation that allows rigid stability, enabling early return of function with excellent rates of union and total active motion. With knowledge of technical pearls presented in this article, common mistakes can be avoided to improve efficiency of screw placement and optimize patient outcomes.

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.