Pisotriquetral arthrodesis for pisotriquetral instability: case report

Carpal dislocations

Carpal dislocations result from sequential disruption of the complex relationship between the bones and ligaments of the wrist. Injuries to the carpus occur via predictable mechanisms, an understanding of which is critical to identify and treat these frequently missed patterns of injury and to avoid the sequela of chronic instability. Lunate dislocations are by far the most common, but isolated dislocation of other carpal bones can also occur. Open reduction and internal fixation still remains the gold standard for treatment regardless of the debate around the specific approaches. These high-energy injuries are associated with significant long-term morbidity even when identified promptly and appropriately treated. This review will focus on the evaluation and management of common forms of carpal dislocations.

Patient Satisfaction with Pisiform Excision for Pisotriquetral Instability or Arthritis: A Prospective Review

Background  Pisotriquetral pain and instability is an elusive cause of ulnar-sided wrist pain. Initial treatment of chronic pisotriquetral pathology should involve a trial of nonoperative therapy such as neutral wrist splint, anti-inflammatories, and intra-articular steroid injections. The mainstay of surgical management of pisotriquetral pain is pisiform excision. Purpose  This prospective study seeks to understand patient satisfaction after pisiform excision in patients with isolated pisotriquetral pathology. Patients and Methods  A consecutive series of nine cases of pisiform excision was performed by the senior surgeon. The primary outcome measure was determined a priori to be the Patient-Rated Wrist Evaluation (PRWE) score. Wrist range of motion, grip strength, and QuickDASH (shortened version of Disabilities of the Arm, Shoulder and Hand) scores were also collected preoperatively and at 3 and 12 months postoperatively as secondary outcome measures. Results  There was a very rapid improvement in the PRWE by 3 months, which was maintained at 12 months. The QuickDASH score was slower to improve, with a significant improvement by 12 months. There was no change in grip strength or wrist range of motion at any time point. Conclusion  Pisiform excision results in a very rapid improvement of symptoms and should be considered in cases of pisotriquetral instability or arthritis that fail conservative management. Level of Evidence  Level IV, case series.

Does pisiform subluxation affect the postoperative outcomes in a cohort of patients with distal radius fractures?

Background

In this study, we retrospectively surveyed the presence or absence of pisiform subluxation in surgically treated distal radius fractures (DRF) cases. In addition, we investigated whether or not the postoperative short-term treatment outcome differs due to the presence of pisiform subluxation.

Materials and methods

The subjects were 134 DRF patients treated with volar locking plate fixation (53 males and 81 females, mean age: 64 years old). The pisotriquetral joint was observed on a preoperative CT to investigate the presence or absence of pisiform subluxation according to the criteria reported by Vasilas. 134 patients divided into subluxation group and non-subluxation group, and the clinical outcomes were compared between these groups.

Results

Pisiform subluxation was noted in 23.1% (31 patients, 15 males and 16 females, mean age 61 years). No significant difference was noted in patient background in both groups. The postoperative pronation angle in the non-subluxation group was significantly greater than that in the subluxation group, but there was no significant difference in any other parameter (the range of motion of the wrist, grip strengths, VAS, Q-DASH scores, and Mayo score) between these 2 groups. However it concomitantly occurred in 23.1% of DRF cases in our series, there was no significant difference in the postoperative treatment outcome between these 2 groups.

Conclusions

Therapeutic intervention of pisiform subluxation is unnecessary during treatment of DRF, since pisiform subluxation does not affect the postoperative clinical outcomes of distal radius fractures.

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Pisiform subluxation occurred in 23.1% of distal radius fracture cases, suggesting that it is not a rare pathology.

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Therapeutic intervention of pisiform subluxation may be unnecessary during treatment of distal radius fracture.

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The therapeutic intervention of pisotriquetral joint disorders should be considered when they develop.

Treatment of Pisotriquetral Arthritis by Pyrocarbon Interposition Arthroplasty

Purpose  Pisiformectomy is the baseline treatment for pisotriquetral arthritis when medical treatment fails to address the problem. This operation may lead to loss of mobility and strength in the wrist. This study reports the short-term outcomes of a new technique for treating pisotriquetral arthritis using a pisotriquetral interposition arthroplasty with a pyrocarbon implant. Patients and Methods  We performed a clinical and radiographic study on a series of eight patients who received this treatment at a mean follow-up of 2.8 years. We also studied the mobility of the implant and did assessed articular instability using dynamic radiology and fluoroscopy. Results  We observed one proximal dislocation of the implant in one hand which was reoperated to reposition the implant and strengthen the capsule. All patients were satisfied or very satisfied with their operation and had an average functional recovery period of 1.6 months. At the last follow-up, the Mayo Wrist Score (MWS), Quick Disability of Arm Shoulder and Hand (QDASH), and Patient-Rated Wrist Evaluation (PRWE) scores were 89, 18, and 20, respectively. Postoperatively, there was a 22% improvement in the grip strength of the wrists as well as improved mobility, mainly as regards the radioulnar deviation (47% improvement) and the Visual Analogue Scale (VAS) pain scores decreased from 8 preoperatively to 2 at the latest follow-up. The functional radiologic and fluoroscopic study reported good adaptive mobility of the implant in all the patients, without any indication of pisotriquetral joint instability. Conclusion  The short-term results of pisotriquetral arthroplasty using the Pyrocardan implant are encouraging. This new surgical solution appears to be a valid alternative to pisiformectomy or pisotriquetral arthrodesis. Long-term studies are required to confirm these preliminary findings.

Management of Pisotriquetral Instability

Pisotriquetral instability is an often-overlooked condition that can lead to ulnar-sided wrist pain and dysfunction. Various case series and biomechanical studies have been published regarding the diagnosis and treatment of this condition. We review current methods for examining, diagnosing, and treating pisotriquetral instability.

Pisotriquetral joint disorders: an under-recognized cause of ulnar side wrist pain

Pisotriquetral joint disorders are often under-recognized in routine clinical practice. They nevertheless represent a significant cause of ulnar side wrist pain. The aim of this article is to present the main disorders of this joint and discuss the different imaging modalities that can be useful for its assessment.

Effect of pisiform excision or pisotriquetral arthrodesis as a treatment for pisotriquetral arthritis: a biomechanical study

PURPOSE

To determine whether flexor carpi ulnaris (FCU) forces and tendon displacements change after pisotriquetral arthrodesis or after pisiform excision.

METHODS

Nine cadaver wrists were moved through 4 variations of a dart throw motion, each having an oblique plane of motion, but with different ranges of motion and different antagonistic forces. The FCU tendon force and movement were measured in the intact wrist, following pisotriquetral arthrodesis, and following pisiform excision. Changes in force and tendon movement were compared using a repeated measures analysis of variance.

RESULTS

After excision of the pisiform, a significantly greater FCU force was required during the 2 variations of the dart throw motion having a larger range of motion and during the smaller motion having a larger antagonistic force. Pisotriquetral arthrodesis did not cause a significant increase in the peak FCU force. Excision of the pisiform caused the FCU tendon to significantly retract during all wrist motions as compared to the intact wrist or after pisotriquetral arthrodesis.

CONCLUSIONS

Greater FCU forces are required to move the wrist when the pisiform with its moment arm function has been removed. This occurs during large oblique plane wrist motions and also in a smaller motion when greater antagonistic forces are applied. Excision of the pisiform also allows the FCU to move proximally, again because its moment arm function has been eliminated.

CLINICAL RELEVANCE

Excision of the pisiform requires greater FCU forces during large wrist motions and during motions that include large gripping forces such that excision may be a concern in high-demand patients with pisotriquetral arthritis. Although pisotriquetral arthrodesis does not alter the mechanical advantage of the FCU, its use in high-demand patients with pisotriquetral osteoarthritis cannot yet be recommended until the effects of that arthrodesis on midcarpal kinematics are further clarified.

Severe ulnar nerve palsy caused by synovial chondromatosis arising from the pisotriquetral joint: a case report and review of literature

We report here the unique case of 60-year-old man with severe ulnar nerve palsy caused by synovial chondromatosis arising from the pisotriquetral joint. At operation, the tumor entrapped the ulnar nerve proximal to the Guyon canal so that it was severely paralyzed. The ulnar neurovascular bundle could be separated safely under the microscope. To our knowledge, this type of severe neuropathy has not been reported before. Although synovial chondromatosis associated with peripheral nerve neuropathy is extremely rare, we should be aware of the existence of this type of compression neuropathy in the upper limb.