O’Driscoll, Shawn W.

Background: The hook test is a sensitive and specific tool that has been previously described for diagnosing distal biceps tendon ruptures in an efficient, cost-effective manner. However, its application in postoperative evaluations after surgical repair of distal biceps tendon ruptures is not documented. Hypothesis/Purpose: We hypothesized that the hook test result returns to normal at some point postoperatively after distal biceps repair. This information could be used in decision making during follow-up examinations with both normal and abnormal findings. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: We retrospectively reviewed records of distal biceps repair. Between July 1, 2003, and July 1, 2016, a total of 56 patients underwent distal biceps repair and also had clear documentation of the results of the hook test during the postoperative period. Hook test results consisted of “intact,” “abnormal,” or “absent.” The timing of the return to a normal hook test result was recorded. Results: Overall, 51 of 57 (89%) repairs were documented to have the hook test result return to “intact.” The test result returned to intact by a mean of 10 weeks after surgery (range, 2 weeks to 15 months). The biceps tendon was intact according to the hook test at the 4-month follow-up in 45 of the 51 patients (88%) in whom it ultimately returned. The hook test result was abnormal in 5 repairs in 5 patients with only a short-term follow-up, ranging from 2 to 7 weeks postoperatively. One patient with an abnormal hook test result at 2 weeks postoperatively underwent revision and was confirmed to have a partial tear of the biceps insertion. His hook test result returned to intact 3 months after revision repair. Conclusion: The hook test result returns to normal in patients who undergo distal biceps repair in the primary and revision settings with adequate follow-up. The vast majority of patients have a normal hook test result by 4 months postoperatively. An abnormal hook test result at 4 months postoperatively may indicate a failed repair and should prompt further investigation.

Background: Safe and effective portal placement is crucial for successful elbow arthroscopy. Various techniques for anterolateral portal placement in elbow arthroscopy have been described, yet radial nerve injuries are commonly reported. Purpose: To report on the technique and safety of anterolateral portal placement by the needle-and-knife method and its clinical applications. Study Design: Case series; Level of evidence, 4. Methods: A retrospective review was completed of patients who underwent an arthroscopic procedure in the anterior compartment of the elbow and anterolateral portal placement. Patients were evaluated immediately postoperatively and at subsequent visits and were monitored for signs of radial nerve injury. Results: A total of 460 patients met the inclusion criteria, of which 309 (67%) underwent the needle-and-knife technique. There was 1 case (0.3%) of temporary radial nerve palsy. For the remaining 151 patients who underwent anterolateral portal placement by other techniques, there were 2 cases of temporary radial nerve palsy (1.3%). There were no cases of the needle-and-knife technique being unsuccessful or abandoned in lieu of a different technique. Use of the needle-and-knife technique increased over time with experience and practice. Initially, contraindications to this technique included impaired view of the lateral side of the anterior compartment of the elbow caused by severe intra-articular scar (65%), extensive synovitis (10%), or large osteophytes or loose bodies (10%). For the remaining patients (15%) who did not have portals placed via the needle-and-knife technique, alternate techniques were used for teaching purposes. Conclusion: The needle-and-knife technique is reproducible and easy to perform by a clinician instructed in its use and trained in elbow arthroscopy. Its main advantage is that it permits the surgeon to safely slide the knife along the lateral supracondylar ridge, releasing the scarred capsule and thereby increasing the available space in which to work. Enlarging the working space inside scarred and contracted elbows cannot be accomplished by distending the capsule.

Aims The aim of this study was to evaluate two hypotheses. First, that disruption of posterior bundle of the medial collateral ligament (PMCL) has to occur for the elbow to subluxate in cases of posteromedial rotatory instability (PMRI) and second, that ulnohumeral contact pressures increase after disruption of the PMCL. Materials and Methods Six human cadaveric elbows were prepared on a custom-designed apparatus which allowed muscle loading and passive elbow motion under gravitational varus. Joint contact pressures were measured sequentially in the intact elbow (INTACT), followed by an anteromedial subtype two coronoid fracture (COR), a lateral collateral ligament (LCL) tear (COR + LCL), and a PMCL tear (COR + LCL + PMCL). Results There was no subluxation or joint incongruity in the INTACT, COR, and COR + LCL specimens. All specimens in the COR + LCL + PMCL group subluxated under gravity-varus loads. The mean articular contact pressure of the COR + LCL group was significantly higher than those in the INTACT and the COR groups. The mean articular contact pressure of the COR + LCL + PMCL group was significantly higher than that of the INTACT group, but not higher than that of the COR + LCL group. Conclusion In the presence of an anteromedial fracture and disruption of the LCL, the posterior bundle of the MCL has to be disrupted for gross subluxation of the elbow to occur. However, elevated joint contact pressures are seen after an anteromedial fracture and LCL disruption even in the absence of such subluxation. Cite this article: Bone Joint J 2018;100-B:1060–5.

Background: Joint incongruity in posteromedial rotatory instability (PMRI) has been theorized to determine early articular degenerative changes. Our hypothesis was that the articular contact area and contact pressure differ significantly between an intact elbow and an elbow affected by PMRI. Methods: Seven cadaveric elbows were tested under gravity varus stress using a custom-made machine designed to simulate muscle loads and allow passive elbow flexion (0° to 90°). The mean contact area and contact pressure data were collected and processed using the Tekscan sensor and software. After testing the intact specimen (intact elbow), a PMRI injury was simulated (PMRI elbow) and the specimen was tested again. Results: The PMRI elbows were characterized by initial joint subluxation and significantly elevated articular contact pressure. Both worsened, corresponding with a reduction in contact area, as the elbow was flexed from 0° until the joint subluxation and incongruity spontaneously reduced (at a mean [and standard error] of 60° ± 5° of flexion), at which point the mean contact pressure decreased from 870 ± 50 kPa (pre-reduction) to 440 ± 40 kPa (post-reduction) (p < 0.001) and the mean contact area increased from 80 ± 8 mm 2 to 150 ± 58 mm 2 (p < 0.001). This reduction of the subluxation was also followed by a shift of the contact area from the coronoid fracture edge toward the lower portion of the coronoid. At the flexion angle at which the PMRI elbows reduced, both the contact area and the contact pressure of the intact elbows differed significantly from those of the PMRI elbows, both before and after the elbow reduction (p < 0.001). Conclusions: The reduction in contact area and increased contact pressures due to joint subluxation and incongruity could explain the progressive arthritis seen in some elbows affected by PMRI. Clinical Relevance: This biomechanical study suggests that the early degenerative changes associated with PMRI reported in the literature could be subsequent to joint incongruity and an increase in contact pressure between the coronoid fracture surface and the trochlea.

We present 12 patients with synovial osteochondromatosis of the elbow treated by synovectomy. Histological review showed that seven cases were primary and five secondary osteochondromatosis. The patients with primary disease had a mean improvement in the flexion arc from a preoperative value of 40° to 123° to 5° to 128° when reviewed at a mean of nine years after operation. The secondary group had a mean improvement in the flexion arc from a preoperative value of 21° to 98° to 4° to 131° at a mean of 6.8 years after operation. There was recurrence in two of seven patients in the primary group and three of five in the secondary group. Osteoarthritis developed in six elbows in the primary and in three in the secondary group. Osteoarthritis secondary to synovial osteochondromatosis is progressive. In the established condition, the distinction between primary and secondary disease may be of greater histological than clinical relevance.

We describe the intermediate results of lateral ligamentous repair or reconstruction for posterolateral rotatory instability of the elbow. Between 1986 and 1999, we performed 12 direct repairs and 33 ligament reconstructions with a tendon autograft. One patient was lost to follow-up and 44 were retrospectively studied at a mean of six years (2 to 15).Surgery restored stability in all except five patients. In two the elbow became stable after a second procedure. The mean post-operative Mayo elbow performance score was 85 points (60 to 100). The result was classified as excellent in 19, good in 13, fair in seven and poor in five patients. Thirty-eight patients (86%) were subjectively satisfied with the outcome of the operation. Better results were obtained in patients with a post-traumatic aetiology (p = 0.03), those with subjective symptoms of instability at presentation (p = 0.006) and those who had an augmented reconstruction using a tendon graft (p = 0.04).Reconstruction using a tendon graft seems to provide better results than ligament repair and the results do not seem to deteriorate with time. The outcome of this procedure is less predictable in patients with no subjective instability.

We used 11 cadaver elbows and a three-dimensional electromagnetic tracking device to record elbow movements before and after implantation of a 'loose-hinged' elbow prosthesis (modified Coonrad). During simulated active motion there was a maximum of 2.7 degrees (+/- 1.5 degrees) varus/valgus laxity in the cadaver joints. This increased slightly after total elbow arthroplasty to 3.8 degrees (+/- 1.4 degrees). These values are lower than those recorded for the cadaver joints and for the prostheses at the limits of their varus/valgus displacements, indicating that both behave as 'semi-constrained' joints under physiological conditions. They suggest that the muscles absorb some of the forces and moments that in a constrained prosthesis would be transferred to the prosthesis-bone interface.

The anatomy of the cubital tunnel and its relationship to ulnar nerve compression is not well documented. In 27 cadaver elbows the proximal edge of the roof of the cubital tunnel was formed by a fibrous band that we call the cubital tunnel retinaculum (CTR). The band is about 4 mm wide, extending from the medial epicondyle to the olecranon, and perpendicular to the flexor carpi ulnaris aponeurosis. Variations in the CTR were classified into four types. In type 0 (n = 1) the CTR was absent. In type Ia (n = 17), the retinaculum was lax in extension and taut in full flexion. In type Ib (n = 6) it was tight in positions short of full flexion (90 degrees to 120 degrees). In type II (n = 3) it was replaced by a muscle, the anconeus epitrochlearis. The CTR appears to be a remnant of the anconeus epitrochlearis muscle and its function is to hold the ulnar nerve in position. Variations in the anatomy of the CTR may explain certain types of ulnar neuropathy. Its absence (type 0 CTR) permits ulnar nerve displacement. Type Ia is normal and does not cause ulnar neuropathy. Type Ib can cause dynamic nerve compression with elbow flexion. Type II may be associated with static compression due to the bulk of the anconeus epitrochlearis muscle.

Objectives: To describe the surgical treatment and patient outcomes of chronic elbow dislocations. Design: Retrospective review. Setting: Two tertiary referral centers. Patients/Participants: All patients with surgically treated chronic elbow dislocation with no associated articular fracture from January 2009 to January 2015. Intervention: Review of patient demographics, injury chronicity, surgical technique, and patient outcomes. Main Outcome Measurement: Clinical outcomes included elbow range of motion and complications. Radiographic outcomes included the presence of heterotopic ossification. Patient-reported outcomes included the Mayo Elbow Performance Index (MEPI) and the Summary Outcome Determination (SOD). Results: Thirty-two patients with mean follow-up of 22 months (range, 13–41 months) were included. The mean dislocation duration was 6 months (range, 1–34 months). The mean preoperative range of motion was 8 degrees (range, 0–30 degrees). There were no infections or recurrent dislocations. One patient developed transient ulnar nerve palsy postoperatively. There were no cases of new or progressive heterotopic ossification. The mean postoperative extension was 31 degrees (range, 0–75 degrees), and the mean postoperative flexion was 132 degrees (range, 95–150 degrees); the mean final arc of motion was 101 degrees (range, 50–140 degrees). The mean postoperative MEPI was 93 (range, 70–100), and the mean SOD score was 9 (range, 6–10). Using the MEPI, 97% (31/32 patients) had good or excellent outcome. There was no difference in flexion/extension arc or MEPI scores between groups of elbows older and younger than 17 years or dislocations less or more than 3 months. Conclusion: This is the largest case series of surgically treated patients with chronic elbow dislocation. Using our surgical technique, 97% of patients had good or excellent outcome with a low complication rate. Open reduction of chronic elbow dislocation can be accomplished while permitting early motion with minimal recurrent dislocation risk. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.