Kakar, Sanjeev

Abstract Background Chronic injuries to the scapholunate ligament (SLIL) alter carpal kinematics and may progress to early degenerative osteoarthritis. To date, there is no consensus for the best method for SLIL reconstruction. This study aims to assess the use of growth factors (bone morphogenetic protein [BMP]2 and growth and differentiation factor 5 [GDF5]) for compartmentalized regeneration of bone and ligament in this multiphasic scaffold in a rabbit knee model. Case Description A total of 100 µg of BMP2 and 30 µg of GDF5 were encapsulated into a heparinized gelatin–hyaluronic acid hydrogel and loaded into the appropriate compartment of the multiphasic scaffold. The multiphasic scaffold was implanted to replace the native rabbit medial collateral ligament (n = 16). The rabbits were randomly assigned to two different treatment groups. The first group was immobilized postoperatively with the knee pinned in flexion with K-wires for 4 weeks (n = 8) prior to sacrifice. The second group was immobilized for 4 weeks, had the K-wires removed followed by a further 4 weeks of mobilization prior to sample harvesting. Literature Review Heterotopic ossification as early as 4 weeks was noted on gross dissection and confirmed by microcomputed tomography and histological staining. This analysis revealed formation of a bony bridge located within and over the ligament compartment in the intra-articular region. Biomechanical testing showed increased ultimate force of the ligament compartment at 4 weeks postimplantation consistent with the presence of bone formation and higher numbers of scaffold failures at the bone–tendon junction. This study has demonstrated that the addition of BMP2 and GDF5 in the bone–ligament–bone (BLB) scaffold resulted in heterotopic bone formation and failure of the ligament compartment. Clinical Relevance The implantation of a three-dimensional-printed BLB scaffold alone demonstrated superior biomechanical and histological results, and further investigation is needed as a possible clinical reconstruction for the SLIL.

Abstract Purpose We have previously described arthroscopic-assisted volar scapholunate (SL) capsulodesis as an alternative technique for addressing volar SL interosseous ligament (SLIL) injuries. In this article, we report the outcomes of this procedure in a cohort of patients. Methods Postoperative outcomes including range of motion, grip strength, visual analog scale (VAS) pain score, Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH), and Mayo Wrist Score were assessed through a prospective review of six patients in a single center who underwent this procedure. Results Six patients (four male and two female) with a mean age of 43 ± 14 years were evaluated in the study. The mean duration of follow-up was 41 ± 17 weeks. Postoperative outcomes noted a reduction in VAS pain score from 8 before surgery to 0.7 postoperatively (p = 0.00004) and improvement in Mayo Wrist Score (42 preoperatively to 80 postoperatively; p = 0.001), grip strength (86% of contralateral side; p = 0.20), and flexion arc (81% of contralateral side; p = 0.08). QuickDASH was 20 ± 8 and Patient-Rated Wrist Evaluation score was 13 ± 2 at the last clinical follow-up. There was an improvement in SL gap (p = 0.03), SL angle (p = 0.11), and radiolunate angle (p = 0.15) measurements postoperatively. Conclusions The described arthroscopic-assisted volar SL capsulodesis in this study presents an alternative method to address volar SLIL pathology with positive short-term clinical outcomes. Clinical Relevance Arthroscopic-assisted volar SL capsulodesis may be considered in the treatment algorithm for volar SLIL injuries.

Abstract Background Spanning bridge plates were first popularized for fixation of complex distal radius fractures. However, indications for their use have expanded including the surgical treatment algorithm for treating conditions such as Kienböck's disease. Traditionally, initial surgical treatment of Lichtman Stages II to III Kienböck's disease included lunate decompression, unloading, and revascularization procedures. The addition of a dorsal spanning bridge plate further facilitates lunate offloading and may improve bone revascularization. Case Description We report a complication of proximal carpal row dorsal subluxation secondary to dorsal spanning plate fixation in a patient with Stage IIIb Kienböck's disease. The patient had undergone wrist arthroscopy, lunate forage, radius core decompression, and spanning plate fixation. At 6 weeks after surgery, radiographic imaging demonstrated dorsal subluxation of the proximal carpal row that was corrected upon bridge plate removal. Serial radiographs during follow-up showed no further carpal subluxation without Kienböck's disease progression at 12 months postremoval of hardware. Patient remains pain free and has returned to elite level sport. Literature Review To our knowledge no previous cases of proximal carpal row subluxation with the use of dorsal bridge plate has been reported in the literature. Clinical Relevance Proximal row carpal subluxation can occur with dorsal bridge plate fixation.

Background: The purpose of this study was to quantify the in vivo displacement of bilateral distal radioulnar joints (DRUJs) in resisted pronosupination. We hypothesize that this will demonstrate no appreciable difference between the left and right DRUJ, thus validating the concept of using the uninjured wrist as a control for physical examination as well as dynamic imaging studies. Methods: Thirty-two participants without a history of wrist pathology underwent a dynamic computed tomography (CT) protocol evaluating bilateral forearm rotation in neutral forearm rotation, 60° pronation, and 60° supination, including maximal isometric muscle loading. The DRUJ alignment, specifically the absolute degree and direction of subluxation of the ulna relative to the sigmoid notch, was then assessed using a modification of the radioulnar line method. Results: There was no significant difference in the mean displacement when comparing the right and left sides in neutral, pronation, or supination. The mean displacement was also compared between male and female patients, and there was no statistically significant difference in absolute displacement in neutral (male 0.99 mm vs female 1.38 mm) or supination (male −0.57 mm vs female −0.23 mm). However, the difference in pronation was statistically significant (male 2.69 mm vs female 3.26 mm). Of the 192 sequences, the measurements of displacement of the authors were within 1 mm 86% of the time (166 of 192). Conclusions: Dynamic CT of bilateral DRUJs in resisted pronation, supination, and neutral demonstrated symmetry between the right and left DRUJ, supporting the concept of using the contralateral side as a control to identify instability in an injured wrist.

AbstractBackground The field of arthroscopy has exponentially grown in the past decade, especially in the realm of upper extremity surgery.Description The use of smaller cameras and further advancements in arthroscopy technology have allowed innovative expansion in the application of arthroscopy in small joints.Clinical Relevance Included in the advancements is the NanoScope, a 1.9-mm flexible scope specifically designed for small joint visualization.

Abstract Background Nanoscope, given its smaller size, may be safer when establishing dorsal wrist arthroscopy portals compared with the traditional 2.7 mm arthroscope. Case Description Ten fresh frozen cadaver specimens were utilized. Dorsal radiocarpal portals were established with the Nanoscope and calipers were used to measure the distance between the portals and the surrounding anatomical structures. The only structure that was pierced during portal placement was the dorsal sensory branch of the ulnar nerve (DSUN) in one specimen when establishing the 6U portal. Our study did not note any tendon injuries. Literature Review Traditional wrist arthroscopy may be performed with a 2.7 mm arthroscope. With its larger outer sheath cannula, this may place adjacent anatomical structures at risk of injury. Clinical Relevance During wrist arthroscopy, the Nanoscope may be safer when creating portals to underlying structures. Level of Evidence This is a Level IV study.

» Ulnar-sided wrist pain is a common cause of debilitating wrist pain in stick-handling athletes. Due to the complexity of surrounding anatomy, the evaluation and diagnosis can be challenging. » Injury of the triangular fibrocartilage complex (TFCC) is the most common cause of ulnar-sided wrist pain. Repetitive, unrestricted pronosupination, wrist deviation, and axial-loading activity, such as in tennis, place substantial stress on the TFCC. » The ulnotriquetral (UT) ligament is a palmar thickening of the ulnar capsule arising from the palmar radioulnar (PRU) ligament of the TFCC. When injured, the UT ligament can be a source of acute or chronic ulnar-sided wrist pain. The ligament can avulse off bone, can rupture completely, or can split longitudinally. » Arthroscopic-assisted repair is a safe, reliable, and effective treatment for UT ligament split tears and peripheral TFCC tears. » Although the benefit of a team-based approach may be realized by most patients, high-performing, stick-handling athletes are part of a unique population who execute repetitive, extraordinary wrist movements. The high demand and functional requirement expected of the wrists require a uniquely tailored approach to return them to the same level of competitive play.

Backgroud: The purpose of this study was to compare the 1,2 with a novel 2R portal in terms of proximity to critical structures. Methods: Wrist arthroscopy was performed on 8 fresh frozen cadavers via the 1,2 and 2R portals. External anatomy was then dissected under loupe magnification. The closest distance between the portals and surrounding anatomical structures was measured in millimeters using digital calipers. Results: The 1,2 portal was significantly closer to radial artery and first extensor compartment tendons than the 2R portal. The radial artery was on average 1.32 mm from the 1-2 portal and 14.25 mm from the 2R portal. The 2R portal was significantly closer to the second and third extensor compartment tendons. The closest branch of the superficial branch of the radial nerve (SBRN) was on average 2.04 mm from the 1-2 portal and 7.59 mm from the 2R portal, but this was not statistically significant. Conclusions: We advocate using the 2R portal preferentially to the 1,2 portal when treating radial sided wrist pathology to decrease the risk of iatrogenic radial artery and SBRN injury.

Background: The objective of this study was to determine whether reconstruction of the proximal pole of the scaphoid with a proximal hamate graft restores native carpal kinematics. Methods: A cadaveric study was designed assessing wrist kinematic after proximal hamate graft for proximal pole of the scaphoid nonunion. Wireless sensors were mounted to the carpus using a custom pin and suture anchor system to 8 cadavers. A wrist simulator was used to move the wrist through a cyclical motion about the flexion/extension and radial/ulnar deviation axes. Each specimen was tested under a series of 3 conditions: (1) a native state, “Intact”; (2) fractured scaphoid proximal pole, “Fracture”; and (3) post-reconstruction of the proximal pole of the scaphoid using a proximal hamate graft, “Graft.” Results: The fracture condition resulted in a statistically significant change in scapholunate kinematics across the entire arc of motion relative to the intact condition. Reconstruction with proximal hamate grafts restored scapholunate kinematics close to the intact state in both flexion/extension and radial/ulnar deviation axes. The lunocapitate flexion during wrist flexion was significantly different after the hamate graft reconstruction. Conclusions: Proximal hamate to scaphoid transfer resulted in restoration of near normal carpal kinematics to the intact state.

Background: An institutional review board–approved study of the functional outcomes of patients after surgical treatment of hamate arthrosis lunotriquetral ligament tear (HALT) lesions was conducted. Methods: In all, 21 wrists in 19 patients underwent arthroscopic, open, or combined treatment of HALT lesions. Seven patients underwent isolated hamate debridement and 14 had concomitant procedures to address lunotriquetral pathology. Nineteen wrists underwent procedures to address additional pathology, including triangular fibrocartilage complex, ulnotriquetral ligament split, and scapholunate ligament injuries. Results: Mayo wrist scores increased from 54 to 71. Sixteen patients had no or mild pain postoperatively, compared with none preoperatively. When stratified by lunotriquetral interosseous ligament management, 75% of the limited treatment group (none or debridement) and 78% of the additional treatment group reported improved pain. Three patients underwent additional surgeries for persistent pain. Conclusion: Resection of the proximal pole of the hamate can improve pain and function for patients with ulnar-sided wrist pain secondary to a HALT lesion. Concomitant wrist pathologies should be considered when determining treatment plans.