Mihir J. Desai

Tendon transfers for radial, median, and ulnar nerve palsy.

Abstract Tendon transfers are used to restore balance and function to a paralyzed, injured, or absent neuromuscular‐motor unit. In general, tendon transfer is indicated for restoration of muscle function after peripheral nerve injury, injury to the brachial plexus or spinal cord, or irreparable injury to tendon or muscle. The goal is to improve the balance of a neurologically impaired hand. In the upper extremity, tendon transfers are most commonly used to restore function following injury to the radial, median, and ulnar nerves. An understanding of the general principles of tendon transfer is important to maximize the outcome.

Major Peripheral Nerve Injuries After Elbow Arthroscopy

PURPOSE To survey the American Society for Surgery of the Hand membership to determine the nature and distribution of nerve injuries treated after elbow arthroscopy. METHODS An online survey was sent to all members of the American Society for Surgery of the Hand under an institutional review board-approved protocol. Collected data included the number of nerve injuries observed over a 5-year period, the nature of treatment required for the injuries, and the outcomes observed after any intervention. Responses were anonymous, and results were securely compiled. RESULTS We obtained 372 responses. A total of 222 nerve injuries were reported. The most injured nerves reported were ulnar, radial, and posterior interosseous (38%, 22%, and 19%, respectively). Nearly half of all patients with injuries required operative intervention, including nerve graft, tendon transfer, nerve repair, or nerve transfer. Of the patients who sustained major injuries, those requiring intervention, 77% had partial or no motor recovery. All minor injuries resolved completely. CONCLUSIONS Our results suggest that major nerve injuries after elbow arthroscopy are not rare occurrences and the risk of these injuries is likely under-reported in the literature. Furthermore, patients should be counseled on this risk because most nerve injuries show only partial or no functional recovery. With the more widespread practice of elbow arthroscopy, understanding the nature and sequelae of significant complications is critically important in ensuring patient safety and improving outcomes.

Arthroscopic Repair of Triangular Fibrocartilage Tears: A Biomechanical Comparison of a Knotless Suture Anchor and the Traditional Outside-In Repairs

PURPOSE To compare the biomechanical strength of a knotless suture anchor repair and the traditional outside-in repair of peripheral triangular fibrocartilage complex (TFCC) tears in a cadaveric model. METHODS We dissected the distal ulna and TFCC from 6 matched cadaveric wrist pairs and made iatrogenic complete peripheral TFCC tears in each wrist. In 6 wrists, the TFCC tears were repaired using the standard outside-in technique using 2 2-0 polydioxane sutures placed in a vertical mattress fashion. In the other 6 wrists, we repaired the TFCC tears using mini-pushlock suture anchors to the fovea. The strength of the repairs was then determined using a materials testing machine with the load placed across the repair site. We loaded the repairs until a gap of 2 mm formed across the repair site, and then subsequently loaded them to failure. Thus, for each repair we obtained the load at 2-mm gap formation, load to failure, and mode of failure. RESULTS At the 2-mm gap formation, the suture anchor repairs were statistically stronger than the outside-in repairs. For load to failure, the suture anchor repairs were also statistically stronger than the outside-in repairs. Failure in both techniques occurred most commonly as suture pull-out from the soft tissues. CONCLUSIONS The all-arthroscopic suture anchor TFCC repair was biomechanically stronger than an outside-in repair. CLINICAL RELEVANCE The suture anchor technique allows for repair of both the superficial and deep layers of the articular disk directly to bone, restoring the native TFCC anatomy. By being knotless, the suture anchor repair avoids irritation to the surrounding soft tissues by suture knots.

Management of Intercarpal Ligament Injuries Associated with Distal Radius Fractures

The prevalence of ligamentous injury associated with fractures of the distal radius is reported to be as high as 69% with injury to the scapholunate interosseous ligament and lunotriquetral interosseous ligament occurring in 16% to 40% and 8.5% to 15%, respectively. There is a lack of consensus on which patients should undergo advanced imaging, arthroscopy, and treatment and whether this changes their natural history. Overall, patients with high-grade intercarpal ligament injuries are shown to have longer-term disability and sequelae compared with those with lower-grade injuries. This article reviews the diagnosis and treatment options for these injuries.

Biomechanical Comparison of Suture-Button Suspensionplasty and LRTI for Basilar Thumb Arthritis:

Background: The purpose of this study was to compare the initial biomechanical strength of trapeziectomy and suture-button suspensionplasty (SBS) with ligament reconstruction and tendon interposition (LRTI) for thumb carpometacarpal (CMC) arthritis in a cadaveric model. Methods: Eight matched pairs of below-elbow cadaveric arms were used for this study. Each specimen was randomly assigned to either receive a trapeziectomy and LRTI (LRTI group) or trapeziectomy and SBS (SBS group). Using previously described and validated testing protocols, physiological key pinch was simulated. The thumb metacarpal was then incrementally loaded from 5 to 20 lbs, using 5-lb increments. Metacarpal subsidence during physiological key pinch and incremental loading was determined using radiographic measurements of trapezial space height. Results: The average pretesting trapezial space height did not differ significantly between the LRTI (11.9 mm) and SBS (13.7 mm) groups. After simulated physiological key pinch, the SBS group had significantly greater average trapezial space height compared with the LRTI group (8.0 mm vs 5.5 mm). For each incremental metacarpal load from 5 to 20 lbs, the SBS group had significantly greater average trapezial space height than the LRTI group. Conclusions: In a cadaveric model, SBS demonstrates greater resistance to metacarpal subsidence with immediate loading compared with LRTI.

Prevalence and Clinical Manifestations of the Anconeus Epitrochlearis and Cubital Tunnel Syndrome

Background: The true prevalence of the anconeus epitrochlearis (AE) and the natural history of cubital tunnel syndrome associated with this anomalous muscle are unknown. The purpose of this study was to evaluate the prevalence of AE and to characterize the preoperative and postoperative features of cubital tunnel syndrome caused by compression from an AE. Methods: All elbow magnetic resonance imaging (MRI) scans and all patients undergoing cubital tunnel surgery during a 20-year period were identified and retrospectively reviewed for the presence of an AE. All patients with an AE identified intra-operatively were matched to patients with no AE identified at surgery based on age, sex, concomitant procedures, and year of surgery. Preoperative and postoperative physical exam findings, electrodiagnostic study results, time to improvement, and reoperations were compared between the groups. Results: A total of 199 patients had an elbow MRI, and 27 (13.6%) patients were noted to have an AE present. Average time to improvement after surgical release was 23.0 days for patients with an AE and 33.2 days for patients with no AE. Twenty-seven patients with an AE noted improvement at the first postoperative visit (68%) compared to 15 patients without an AE (33%). No patients with an AE underwent reoperation for recurrent symptoms (0%) compared with four patients (10%) without an AE. Conclusions: The prevalence of AE in our study is 13.6%. These patients experience quicker and more reliable symptom improvement after surgical release than those without the anomalous muscle.

Radial to Axillary Nerve Transfers: A Combined Case Series

PURPOSE Loss of active shoulder abduction after brachial plexus or isolated axillary nerve injury is associated with a severe functional deficit. The purpose of this 2-center study was to retrospectively evaluate restoration of shoulder abduction after transfer of a radial nerve branch to the axillary nerve for patients after brachial plexus or axillary nerve injury. METHODS Patients who underwent transfer of a radial nerve branch to the anterior branch of the axillary nerve between 2004 and 2014 were reviewed. A total of 27 patients with an average follow-up of 22 months were included. Outcome measures included pre- and postoperative shoulder abduction and triceps strength and active and passive shoulder range of motion. RESULTS Shoulder abduction strength increased after surgery in 89% of patients. Average preoperative shoulder abduction was 12° compared with 114° after surgery. Twenty-two of 27 patients (81.5%) achieved at least M3 strength, with 17 of 27 patients (62.9%) achieving M4 strength. No differences were observed when subgroup analysis was performed for isolated nerve transfer versus multiple nerve transfer, mechanism of injury, injury level, branch of radial nerve transferred, or time from injury to surgery. A negative correlation was found comparing increasing age and both shoulder abduction strength and active shoulder abduction. No patients lost triceps strength after surgery. There were 4 patients who achieved no significant gain in shoulder abduction or deltoid strength and were deemed failures. No postoperative complications occurred. CONCLUSIONS Transfer of a branch of the radial nerve to the anterior branch of the axillary nerve was successful in improving shoulder abduction strength and active shoulder motion in the majority of the patients with brachial plexus or isolated axillary nerve injury. TYPE OF STUDY/LEVEL OF EVIDENCE Therapeutic IV.

Biomechanical Strength of Scaphoid Partial Unions

Background It remains unknown how much force a partially united scaphoid can sustain without refracturing. This is critical in determining when to discontinue immobilization in active individuals. Purpose The purpose of this study was to test the biomechanical strength of simulated partially united scaphoids. We hypothesized that no difference would exist in load‐to‐failure or failure mechanism in scaphoids with 50% or more bone at the waist versus intact scaphoids. Materials and Methods Forty‐one cadaver scaphoids were divided into four groups, three experimental osteotomy groups (25, 50, and 75% of the scaphoid waist) and one control group. Each was subjected to a physiologic cantilever force of 80 to 120 N for 4,000 cycles, followed by load to failure. Permanent deformation during physiologic testing and stiffness, max force, work‐to‐failure, and failure mechanism during load to failure were recorded. Results All scaphoids survived subfailure conditioning with no significant difference in permanent deformation. Intact scaphoids endured an average maximum load to failure of 334 versus 321, 297, and 342 N for 25, 50, and 75% groups, respectively, with no significant variance. There were no significant differences in stiffness or work to failure between intact, 25, 50, and 75% groups. One specimen from each osteotomy group failed by fracturing through the osteotomy; all others failed near the distal pole loading site. Conclusion All groups behaved similarly under physiologic and load‐to‐failure testing, suggesting that inherent stability is maintained with at least 25% of the scaphoid waist intact. Clinical Relevance The data provide valuable information regarding partial scaphoid union and supports mobilization once 25% union is achieved.

Heterotopic Ossification After the Arthroscopic Treatment of Lateral Epicondylitis

Background: Heterotopic ossification (HO) is a well-known complication following the surgical treatment of fractures and dislocations about the elbow but it is not commonly discussed as a complication following arthroscopy. We present a case of a young athlete who developed HO after the arthroscopic treatment of lateral epicondylitis. Methods: This is a case report chart review of a 24 year old male with lateral epicondylitis. After failing conservative measures, arthroscopic debridement of the extensor carpi radialis brevis (ECRB) origin ensued. The treatment and patient’s final disposition were reported. Results: The patient developed heterotopic ossification of the elbow follow arthroscopic debridement of the ECRB origin. Further surgery was required to excise the heterotopic ossification. Good recovery of motion was achieved. Conclusion: To our knowledge, we present the first case of HO development after elbow arthroscopy for lateral epicondylitis. As the use of elbow arthroscopy continues to grow, there is a need for identification of the risk factors and primary prophylaxis for HO.

Median Nerve Compression by Radial Head Osteophyte

Congenital radial head dislocations are rare, and presentation with late complications is even less common. We present a case of a patient who presented with symptoms and findings of proximal median nerve compression secondary to large osteophytes associated with untreated congenital radial head dislocations.