Safe Drill Trajectory for Anatomic Repair of Distal Biceps Tendon Through a Single Incision: A Cadaveric Study.

PURPOSE: We sought to determine the safest drill trajectory to avoid injury to the posterior interosseous nerve (PIN) when performing a repair of a distal biceps tendon to an anatomic location through an anterior, single-incision approach using cortical button fixation. METHODS: A standard anterior approach was performed in 10 cadaveric specimens to expose the distal biceps attachment. Three drill holes were made in the radial tuberosity from the center of the anatomic footprint for the distal biceps tendon insertion with the forearm fully supinated. Holes were made in 30° distal, transverse, and 30° proximal directions. Each hole was made by angling the trajectory from an anterior to posterior and ulnar to radial direction, leaving adequate bone on the ulnar side to accommodate an 8-mm tunnel for the purpose of docking the biceps tendon into bone. The proximity of each drill trajectory to the PIN was determined by making a second incision on the dorsum of the proximal forearm. A K-wire was passed through each hole, and the distance between the PIN and K-wire was measured for each trajectory. RESULTS: The distally directed drill hole placed the trajectory wire closest to the PIN (mean distance, 5.4 mm), contacting the K-wire in 3 cases. The transverse drill trajectory resulted in contact with the PIN in 1 case (mean distance, 7.6 mm). The proximal drill trajectory appeared safest, with no PIN contact (mean distance, 13.3 mm). CONCLUSIONS: In this cadaveric study, the proximal drill trajectory resulted in the widest clearance from the PIN. CLINICAL RELEVANCE: When performing repair of a distal biceps tendon to the anatomic location on the tuberosity, the drill trajectory from the center of the biceps footprint should be radial and proximal to provide the greatest separation between the drill guide and the PIN.

The coronoid opening angle: a novel radiographic technique to assess bone loss in coronoid trauma.

BACKGROUND: Elbow fracture dislocations are complex injuries that often require surgical treatment in order to obtain a stable and congruent elbow joint. The coronoid plays a key role in the stability of this joint. Accurately identifying the degree of coronoid bone loss in the setting of traumatic elbow injuries is challenging. The purpose of this study is to describe a new radiographic measure, the coronoid opening angle (COA), to assist in estimating bone loss in these challenging fractures. METHODS: Radiographs were drawn from a regional database in a consecutive fashion. Candidate radiographs were excluded on the basis of radiographic evidence of degenerative changes, previous surgery or injury, bony deformity, and inadequate lateral view of the elbow. Normal COA, coronoid height, and calculated COA at varying amounts of bone loss were determined by 3 reviewers. RESULTS: A total of 120 subjects were included. The normal coronoid opening angle was 34° (95% CI 32.9°-34.0°) and the coronoid height, 18.8 mm (18.1-19.6). Ninety-five percent of the population had an opening angle greater than 29° (95% CI 27.2°-29°). The COA limit was calculated at 20%, 33%, and 50% of baseline coronoid height corresponding to degree of bone loss. Coronoid opening angles of 24°, 20°, and 16°, respectively, indicate the minimum bone loss of interest in 95% of the population. The intraclass correlation coefficient was found to be 0.89 or higher. CONCLUSION: In the setting of elbow trauma, it is often challenging to predict the amount of coronoid bone loss. The coronoid opening angle is a new technique and an adjunct for lateral elbow radiographs to predict the minimum coronoid bone loss. This can be used to guide clinical decision making, aid in predicting instability, and guide treatment. Future research will aim to validate this tool in the clinical trauma setting.

Analysis of Radiographic Relationship between Distal Radius, Ulna, and Lunate.

Background Wrist anatomy variability is associated with differing susceptibility to pathology. For example, a flat radial inclination is associated with Kienbock's disease. Lunate facet inclination (LFI) also exhibits variability. Its relationship with other wrist features is poorly documented. Purposes We tested the hypothesis that high LFI is associated with increased uncovering of the lunate, negative ulnar variance (UV), and type 2 lunates to balance forces across wrists. Methods In total, 50 bilateral and 100 unilateral wrist posteroanterior radiographs were reviewed. Lunate type, lunate uncovering index (LUI), lunate tilting angle (LTA), UV, and sigmoid notch angle (SNA) were measured, and correlation with LFI was assessed on 150 right wrist radiographs followed by an assessment of differences based on lunate morphology. Symmetry of 50 bilateral wrists was assessed. Results There was no correlation of LFI with lunate morphology, LUI, and LTA. There was a low correlation of LFI with SNA and UV. There was an inverse relationship between UV and SNA. Wrists with type 2 lunates had more oblique sigmoid notches and higher LTA in comparison to wrists with type 1 lunates. Side-to-side comparison revealed strong correlation except for LUI, which exhibited moderate correlation. Conclusions There is no correlation between LFI, LUI, and lunate morphology. Type 2 lunates are associated with higher LTA and more oblique SNA. Wrists were symmetrical. Clinical Relevance Factors other than lunate morphology are essential in balancing forces across wrists. A better understanding of soft tissue and other factors will improve the understanding of wrist biomechanics and pathology. Contralateral wrist radiographs can guide reconstructive surgery.

Clinical and Radiographic Correlates for the Treatment of Ulnocarpal Impaction.

Background Ulnocarpal impaction (UCI) is a described cause of ulnar side wrist pain. Questions Does absolute ulnar variance (UV) or change in UV with grip affect patient-rated outcome scores (PROS) in patients with symptomatic UCI undergoing surgery? Does UV differ between symptomatic and contralateral wrists? Does arthroscopic grade of triangular fibrocartilaginous complex (TFCC) tears and lunotriquetral (LT) ligament tears influence PROS? Do PROS improve following ulnar shortening osteotomy (USO) or wafer procedures and does improvement depend on the amount of shortening or achievement of negative UV? Patients and Methods We analyzed information on patients undergoing USO or wafer procedures for UCI as recorded in a database of prospectively collected information on individuals with ulnar side wrist pain. This included (1) patient-rated wrist evaluation and QuickDASH scores on enrolment, 3 and 12 months postoperatively; (2) standardized bilateral posteroanterior (PA) wrist radiographs, including PA grip views of the symptomatic wrist; and (3) arthroscopic findings. Results Larger changes in UV between PA neutral and grip views prior to surgery were associated with smaller improvements in PROS, 12 months after surgery. Actual UV value before and after surgery did not affect PROS. There was no difference in UV between symptomatic and contralateral wrists. The presence of TFCC or LT ligament tears did not influence PROS. Mean PROS improved postoperatively. Conclusions Ulnar shortening procedures result in improvement in PROS in patients with UCI. Variation in UV with rotation and grip results in variable outcomes. Level of Evidence This is a Level II, cohort study.

Hamstrings tendon graft preparation for anterior cruciate ligament reconstruction using the WhipKnot™ soft tissue cinch technique.

BACKGROUND: Appropriate graft tension and secure graft incorporation in bone tunnels are essential for successful anterior cruciate ligament (ACL) reconstruction using hamstrings tendon autografts. The WhipKnot™ soft tissue cinch, introduced by Smith and Nephew in 2004, is an alternative option to the commonly used whipstitch technique during preparation of the hamstring autograft in ACL reconstruction. AIMS: To investigate the effectiveness of the WhipKnot™ soft tissue cinch and technique during the preparation of the tendon graft for ACL reconstruction. METHOD: A total of 33 ACL reconstruction operations performed between February 2011 and December 2011 were included in this study. These were performed by a single senior surgeon who used the Whipknot™ technique for the preparation of each graft. Four were used for each operation; two for each end of the harvested hamstrings tendons, including semitendinosus and gracilis tendons respectively. RESULTS: In total, 132 WhipKnots were used during the knee operations. Use of the WhipKnot™ technique resulted in successful graft preparations, tensioning and effective graft placement in the tibial and femoral tunnels in almost all instances. Only one case of WhipKnot™ failure (slippage) was recorded. CONCLUSION: These results indicate that the Whipknot™ technique is a safe, reliable and practical option for the preparation of the hamstrings autografts.