Postoperative Pain Is Correlated with Scaphoid Dorsal Translation following Scapholunate Interosseous Ligament Reconstruction.

Background Dorsal scaphoid translation (DST) has been demonstrated to occur in patients with complete scapholunate interosseous ligament (SLIL) tears. Radiographs and magnetic resonance imaging (MRI) have demonstrated ability to detect DST in patients with documented complete scapholunate (SL) disruption, but the relevance of this parameter to outcomes of reconstruction has not been determined. Purpose The purpose of this article is to determine how radiographic parameters of SL dissociation correlate with postoperative pain and functional outcomes of SLIL reconstruction. Methods We performed a retrospective review of prospectively collected data on a cohort of 14 patients who underwent SLIL repair or reconstruction. Preoperative data included radiographic measurements of carpal posture and alignment (SL angle, radiolunate [RL] angle, SL gap, and DST), self-reported measure of average pain on a numerical rating scale (NRS) of 0 to 10, and the patient rated wrist evaluation (PRWE) survey. Postoperatively, the same data were collected at each follow-up visit. Radiographic parameters were statistically compared with postoperative NRS pain score and PRWE scores. Statistical correlations were calculated using Spearman's correlation coefficient, and mean NRS pain scores were compared using Wilcoxon's rank-sum tests, with an α value of p = 0.05. Results Mean NRS pain scores improved significantly after surgery. Mean DST improved significantly after surgery. The presence of postoperative dorsal scaphoid translation (DST) correlated strongly with postoperative pain. SL angle, RL angle, and SL gap showed no correlation with patient reported pain. There was no correlation with any radiographic parameter and PRWE. Conclusions Our study demonstrates that the presence of DST in postoperative radiographs has a strong correlation with patient reported pain following SLIL reconstruction. We conclude that correction of dorsal translation of the scaphoid is a more sensitive predictor of postoperative pain relief than SL gap, RL angle, or SL angle. Level of evidence This is a Level IV study.

Role of Ligament Stabilizers of the Proximal Carpal Row in Preventing Dorsal Intercalated Segment Instability: A Cadaveric Study.

BACKGROUND: Isolated injuries of the scapholunate interosseous ligament (SLIL) are insufficient to produce dorsal intercalated segment instability. There is no consensus about which additional ligamentous stabilizers are critical determinants of dorsal intercalated segment instability. The aim of this study was to evaluate the role of the long radiolunate (LRL), scaphotrapeziotrapezoid (STT), and dorsal intercarpal (DIC) ligaments in preventing dorsal intercalated segment instability. METHODS: Thirty fresh-frozen forearms were randomized to 5 ligament section sequences to study the SLIL, LRL, STT, and DIC ligaments. The DIC-lunate insertion (DIC) and scaphoid insertion (DIC) were studied separately; the DIC insertions on the trapezium and triquetrum were left intact. Loaded posteroanterior and lateral fluoroscopic images were obtained at baseline and repeated after each ligament was sectioned. After each sequence, the wrists were loaded cyclically (71 N). The radiolunate angle was measured with load. Dorsal intercalated segment instability was defined as an increase of >15° in the radiolunate angle compared with baseline. RESULTS: Division of the SLIL did not increase the radiolunate angle. Section of the SLIL+LRL or SLIL+DIC significantly increased the radiolunate angle but did not produce dorsal intercalated segment instability. Section of the SLIL+STT or SLIL+DIC+DIC produced dorsal intercalated segment instability. CONCLUSIONS: In order to produce dorsal intercalated segment instability, complete scapholunate injuries require the disruption of at least 1 critical ligament stabilizer of the scaphoid or lunate (the STT or DIC+DIC). CLINICAL RELEVANCE: When treating SLIL tears with dorsal intercalated segment instability, techniques to evaluate the volar and dorsal critical stabilizers of the proximal carpal row should be considered.

Radiographs Detect Dorsal Scaphoid Translation in Scapholunate Dissociation.

Background Dorsal translation of the proximal scaphoid pole onto the rim of the distal radius is a late finding associated with chronic scapholunate instability. Dorsal scaphoid translation (DST) has been identified by magnetic resonance imaging in patients with scapholunate dissociation (SLD). Purpose The authors proposed to determine whether DST can be reliably detected on radiographs using two different measurement techniques. Patients and Methods Lateral radiographs of 20 patients with operatively confirmed SLD were compared with 20 uninjured patients in blinded assessment. DST was assessed using the concentric circle and dorsal tangential line methods. Reliability was calculated using intraclass correlation (ICC) values. Results Using both techniques, the scaphoid demonstrated increased dorsal translation in patients with SLD. Inter-rater reliabilities for the concentric circles and dorsal tangential line method on radiographs had ICCs > 0.80. Similarly, intra-rater reliabilities had ICCs > 0.90. Conclusions Both the concentric circles and dorsal tangential line techniques had excellent reliabilities, but the dorsal tangential line method is clinically more practical. Type of Study/Level of Evidence This is a Level III, diagnostic study.

Evaluation of two collagen conduits and autograft in rabbit sciatic nerve regeneration with quantitative magnetic resonance DTI, electrophysiology, and histology.

BACKGROUND: We compared different surgical techniques for nerve regeneration in a rabbit sciatic nerve gap model using magnetic resonance diffusion tensor imaging (DTI), electrophysiology, limb function, and histology. METHODS: A total of 24 male New Zealand white rabbits were randomized into three groups: autograft (n = 8), hollow conduit (n = 8), and collagen-filled conduit (n = 8). A 10-mm segment of the rabbit proximal sciatic nerve was cut, and autograft or collagen conduit was used to bridge the gap. DTI on a 3-T system was performed preoperatively and 13 weeks after surgery using the contralateral, nonoperated nerve as a control. RESULTS: Overall, autograft performed better compared with both conduit groups. Differences in axonal diameter were significant (autograft > hollow conduit > collagen-filled conduit) at 13 weeks (autograft vs. hollow conduit, p = 0.001, and hollow conduit vs. collagen-filled conduit, p < 0.001). Significant group differences were found for axial diffusivity but not for any of the other DTI metrics (autograft > hollow conduit > collagen-filled conduit) (autograft vs. hollow conduit, p = 0.001 and hollow conduit vs. collagen-filled conduit, p = 0.021). As compared with hollow conduit (autograft > collagen-filled conduit > hollow conduit), collagen-filled conduit animals demonstrated a nonsignificant increased maximum tetanic force. CONCLUSIONS: Autograft-treated rabbits demonstrated improved sciatic nerve regeneration compared with collagen-filled and hollow conduits as assessed by histologic, functional, and DTI parameters at 13 weeks.

Radial styloidectomy for scaphoid nonunion advanced collapse - relevance of nonunion location.

Radial styloidectomy along with scaphoid nonunion reconstructive surgery is considered an acceptable surgical treatment for stage 1 scaphoid nonunion advanced collapse. The extent of radioscaphoid joint wear that defines scaphoid nonunion advanced collapse stage 1 is unclear. An appropriate radial styloidectomy is limited to 6 mm styloid removal to prevent carpal instability. The aim of this study was to determine whether nonunion fracture location can be a guiding factor in determining whether the scaphoid bone can be retained with scaphoid nonunion reconstructive surgery and radial styloidectomy. We reviewed wrist radiographs and magnetic resonance imaging studies of 21 patients with a diagnosis of scaphoid nonunion advanced collapse stage 1, and quantified chondral wear as the length of a line (in mm) along the radioscaphoid joint traced from the tip of the radial styloid to the most ulnar position along the radioscaphoid joint. We concluded that scaphoid nonunion reconstructive surgery with radial styloidectomy is only appropriate for nonunions in the distal or middle third of the scaphoid. LEVEL OF EVIDENCE: III.

Comparative survival analysis of porous tantalum and porous titanium acetabular components in total hip arthroplasty.

BACKGROUND: Porous tantalum acetabular components (PoTa) are well-studied, but less is known about widely used porous titanium (PoTi) acetabular components. We performed a comparative survival analysis between PoTi and PoTa acetabular components. METHODS: Primary or revision THA performed using PoTi (n = 2,976) or PoTa (n = 184) acetabular components with minimum 2-year follow-up (PoTi n = 1,539; PoTa n = 157) were analysed. Univariate and multivariate logistic regression were performed to test the effect of porous metal acetabular component type on revision surgery for aseptic cup loosening. Multivariate model was adjusted for acetabular defect severity according to the Paprosky Classification. RESULTS: Only PoTi components used in revision THA failed. Survival of the PoTi acetabular component was 98.6% when used in revision THA at mean 48.3-month follow-up. After adjusting for severity of acetabular defect, there was no difference in survival between PoTi and PoTa acetabular components when used in primary or revision THA. CONCLUSIONS: After adjusting for acetabular defect severity, both PoTa and PoTi acetabular components had excellent survival at mean 44.4-month (range 4.3-91.5 months) follow-up when used in primary and revision THA.