Scapholunate Advanced Collapse: Motion-Sparing Reconstructive Options

Force Transfer through the Scaphotrapeziotrapezoid (STT) Joint

Background  The scaphotrapeziotrapezoidal (STT) joint transfers forces to the proximal carpal row from the thumb and fingers. Clinically, STT joint osteoarthritis is frequently observed on plain radiographs though its role in the mechanics of the wrist joint remains unclear. Questions/Purposes  Our purpose was to use a model of normal wrist types, to predict STT motion upon load. Patients and Methods  Five normal computed tomography scans of a wrist type 1 and five wrist type 2 were used to model the wrist. A 200-N force was split and applied to the trapezoid and capitate to replicate forces during a knuckle pushup. The bony movement was predicted by the model as bony movement using finite element analysis. Results  We found differences in force transfer through the STT joint between the two wrist types when loading the index and middle fingers. Type 1 wrists moved quantitatively more anterior-posterior, type 2 wrists moved more medially-laterally and more proximally-distally. The trapezium in type 1 wrists moved more in the coronal plane than in type 2 wrists. The trapezoid moved more from distal to proximal in a type 2 wrist, p  = 0.03. Conclusion/Clinical Relevance  This study found differences in motion upon loading through the STT joint between type 1 and 2 wrists. Type 2 wrists moved more radially toward the proximal scaphoid and scapholunate ligament. This study may provide a mechanical basis for degenerative configurations. By linking observed patterns of degeneration to their mechanical causes we can aid in prevention of arthritis.

The Biomechanical Effects of Simulated Radioscapholunate Fusion With Distal Scaphoidectomy, 4-Corner Fusion With Complete Scaphoidectomy, and Proximal Row Carpectomy Compared to the Native Wrist

PURPOSE

To determine the effect of simulated radioscapholunate fusion with distal scaphoid excision (RSLF+DSE), 4-corner fusion with scaphoidectomy (4-CF), and proximal row carpectomy (PRC) on the wrist's range of motion (ROM), contact pressure, and contact force in a cadaveric model.

METHODS

Ten freshly frozen cadaveric wrists were tested under 4 sequential conditions: native wrist, RSLF+DSE, 4-CF, and PRC. The simulated fusions were performed using two 1.6-mm Kirschner wires. The ROM in the flexion-extension and radioulnar deviation planes was evaluated. Contact area, contact pressure, and contact force were measured at the scaphocapitolunate joint for the RSLF+DSE simulation and radiocarpal joint for the 4-CF and PRC simulations. Mechanical testing was performed using a 35-N uniaxial load and pressure-sensitive film.

RESULTS

The RSLF+DSE and 4-CF groups had a decreased wrist arc ROM compared with the native wrist. The PRC group had a greater wrist arc ROM compared with the RSLF+DSE and 4-CF groups, but compared to the native wrist, it demonstrated a mildly decreased wrist arc ROM. The carpal pressure and contact force were significantly increased in the RSLF+DSE, 4-CF, and PRC groups compared with those in the native wrist. The RSLF+DSE group had the smallest increase in the carpal pressure and contact force, whereas the PRC group had the greatest increase.

CONCLUSIONS

Our study validates previous findings that PRC is motion-conserving but has the greatest contact force, whereas RSLF-DSE and 4-CF may cause a decrease in the ROM but have lower contact forces.

CLINICAL RELEVANCE

Understanding the underlying native wrist biomechanics and alterations following different surgical treatments may assist hand surgeons in their clinical decision making for the treatment of stage II scapholunate advanced collapse.

Post-traumatic Scapholunate Advanced Collapse of the Wrist: A Case Report

Objective

The purpose of this report is to describe a patient with scapholunate advanced collapse (SLAC) of the wrist.

Clinical Features

A 38-year-old man presented to a chiropractic teaching clinic with right wrist pain after falling off of the tailgate of a truck 7 years prior. The mechanism of injury was a fall on an outstretched hand. Ultrasonography and radiography were performed, which demonstrated abnormal lunate kinematics and scapholunate interval diastasis associated with a clenched-fist maneuver. These findings were consistent with SLAC.

Intervention and Outcome

Following the diagnosis of SLAC, the wrist was splinted. Conservative care consisting of physical therapy included paraffin dips, therapeutic ultrasound, and stretching. The patient received only minimal alleviation of pain, and a surgical consultation was obtained. The patient elected surgical intervention, utilizing the proximal row carpectomy procedure.

Conclusion

This case demonstrates a patient with chronic wrist pain, with progression to carpal instability, which ultimately manifested as SLAC. We demonstrate, utilizing multiple imaging modalities, both preoperative and postoperative findings. To our knowledge, this is the first case to describe the use of diagnostic ultrasonography in the evaluation of the proximal row carpectomy procedure.

Mid-term outcomes of routine proximal row carpectomy compared with proximal row carpectomy with dorsal capsular interposition arthroplasty for the treatment of late-stage arthropathy of the wrist

AIMS

The aims of this study were to compare the mid-term outcomes of patients with late-stage arthritis of the wrist treated with proximal row carpectomy (PRC) and dorsal capsular interposition (DCI) arthroplasty with a matched cohort treated with routine PRC alone.

PATIENTS AND METHODS

A total of 25 arthritic wrists (24 patients) with pre-existing degenerative changes of the proximal capitate and/or the lunate fossa of the radius were treated with PRC + DCI over a ten-year period. This group of patients were matched 1:2 with a group of 50 wrists (48 patients) without degenerative changes in the capitate or lunate fossa that were treated with a routine PRC alone during the same period. The mean age of the patients at the time of surgery was 56.8 years (25 to 81), and the demographics and baseline range of movement of the wrist, grip strength, Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score, and Patient-Rated Wrist Evaluation (PRWE) score were similar in both groups.

RESULTS

At a mean follow-up of 5.9 years (1.8 to 11.8), significant improvements in mean grip strength, the flexion-extension arc of movement of the wrist, QuickDASH, and PRWE scores were seen in both groups. There was no diifference between the groups for any of the outcomes. One patient in the PRC + DCI group required additional surgery for a deep infection, while two in the PRC group had complications (one wound dehiscence requiring revision closure, one transient radial sensory neuritis). One patient in each group required total arthrodesis of the wrist for progressive degenerative radiocarpal changes. A total of 70 patients (93%) were satisfied with the outcomes.

CONCLUSION

PRC with DCI is an effective form of treatment for late-stage arthritis of the wrist involving the capitolunate joint, with mid-term outcomes that are similar to those in patients without degenerative changes affecting the capitate or lunate fossa who are treated with a routine PRC alone. Cite this article: Bone Joint J 2018;100-B:197-204.

Four-Year Outcomes of Midcarpal Hemiarthroplasty for Wrist Arthritis

PURPOSE

The purpose of this study was to review the average 4-year outcomes of a cohort of patients with wrist arthritis, treated by a single surgeon with a novel prosthetic hemiarthroplasty of the midcarpal joint. We hypothesized that midcarpal hemiarthroplasty would improve range of motion and grip strength of patients with wrist arthritis, with a complication profile comparable with that of alternative solutions for wrist arthritis.

METHODS

We reviewed a series of 20 patients treated with a midcarpal hemiarthroplasty at an average of 4 years following surgery. Patients were evaluated objectively with grip strength, wrist range of motion, serial radiographs, and subjectively surveyed with Disabilities of the Arm, Shoulder, and Hand (DASH) and Mayo scores.

RESULTS

Range of motion increased by a mean 33° in flexion-extension and 10° in radial-ulnar deviation compared with preoperative range of motion. Mean grip strength improved to 20.8 kg from 14.1 kg, and Mayo and DASH scores also significantly improved. Three patients had a manipulation under anesthesia for stiffness. One patient required open reduction internal fixation of an unstable fourth carpometacarpal joint after falling. Two patients were revised to a total wrist arthroplasty and 1 to a wrist fusion.

CONCLUSIONS

Midcarpal hemiarthroplasty provides improved wrist range of motion, grip strength, and patient-reported outcome scores compared with preoperative values, with a complication profile comparable with that of other surgical options for patients with wrist arthritis. Advantages of midcarpal arthroplasty include retention of the native distal carpal row, preservation of midcarpal motion, as well as the option for conversion to a total wrist arthroplasty should revision be required.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

A Comparative Analysis of Resource Utilization Between Proximal Row Carpectomy and Partial Wrist Fusion: A Population Study

PURPOSE

We conducted a population-level analysis comparing proximal row carpectomy (PRC) and partial wrist arthrodesis (PWA) for treatment of chronic wrist arthritis to (1) characterize national practice patterns, (2) determine the rate of conversion to total wrist arthrodesis (TWA), and (3) calculate the associated direct cost of care.

METHODS

Using the Truven MarketScan databases from 2009 to 2015, we identified patients 18 years or older with a diagnosis of wrist osteoarthritis who had a PRC or PWA and were followed for 18 months. We used Chi-square analysis and multivariable logistic regression to examine patient characteristics associated with conversion to a TWA. Rates of repeat PWA were also obtained, including the total number of procedures until completion and direct treatment cost.

RESULTS

Of a total of 3,388 eligible patients, 1,305 had a PRC (39%) and 2,083 had a PWA (61%). In patients 54 years of age or younger, PWA was more commonly performed than PRC (49% vs 38%). The TWA rates were significantly higher for patients of all ages who underwent PWA (19.2%) versus PRC (4.9%). Those undergoing PWA required more total procedures than patients who received a PRC (average, 1.7 vs 1.1) resulting in a greater average direct cost per patient ($10,842 vs $7,171).

CONCLUSIONS

Conversion rates to a TWA are significantly higher with a PWA (19.2%) than with a PRC (4.9%) and have a greater associated direct cost. This includes younger patients, who in the past were considered better candidates for PWA. Our findings suggest that surgeons may need to reevaluate their indications for PWA and that there may need to be a paradigm shift in the current practice patterns for salvage treatment of wrist arthrosis, more often considering PRC for all age groups.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic II.

Update on the operative treatment of scapholunate instability for radiologists. II. Salvage procedures, total wrist arthrodesis, and total wrist arthroplasty

Scapholunate (SL) instability is the most common form of carpal instability. Imaging (especially radiography) plays an important role in the staging, management, and postoperative follow-up of SL instability. In the final stage of SL instability, known as scapholunate advanced collapse, progressive degenerative changes occur at the carpal level. The goals of this article are to review the surgical options available for addressing the different stages of scapholunate advanced collapse, along with an emphasis on normal postoperative imaging and complications associated with each surgical option.

Stage III Advanced Wrist Collapse Treatment Options: A Cadaveric Study

Background Scapholunate advanced collapse and scaphoid nonunion advanced collapse result in high morbidity and pose significant challenges for active patients. Multiple treatment options have been proposed to yield satisfactory results; however, restoration of physiological wrist motion remains an issue. Questions/Purposes The objective of this study was to compare wrist mobility after four different treatment methods for grade III wrist collapse: (1) no treatment, (2) scaphoidectomy and lunate-capitate arthrodesis, (3) scaphoidectomy, lunate-capitate arthrodesis, and triquetrum-hamate arthrodesis, and (4) scaphoidectomy, lunate-capitate arthrodesis, and triquetrum excision. Methods Four paired (n = 8) fresh-frozen human cadaveric upper limbs were used in this controlled laboratory study. Computed tomography scans were collected at all testing states and measurements were made to evaluate midcarpal joint mobility and alignment. Results A significant decrease in wrist extension was observed for all treatments. Middle column and two-column arthrodesis demonstrated no significant differences for carpal alignment and mobility. No significant differences were observed for triquetrum-hamate mobility or wrist extension between the partial and two-column arthrodesis. Triquetrum excision significantly improved ulnar deviation. Conclusion The most important finding of this study was that the one-column arthrodesis has comparable carpal alignment and range of motion to that of bi-column arthrodesis. Clinical Relevance The results of this study suggest that a stage III advanced wrist collapse can be treated by isolated lunate-capitate arthrodesis with scaphoidectomy. Fusion between the remaining carpal bones may not be necessary because the carpal alignment and range of motion of the remaining joints were not significantly different in the present study.