Biomechanical Analysis of Palmar Midcarpal Instability and Treatment by Partial Wrist Arthrodesis.

PURPOSE: To create a biomechanical model of palmar midcarpal instability by selective ligament sectioning and to analyze treatment by simulated partial wrist arthrodesis. METHODS: Nine fresh-frozen cadaver arms were moved through 3 servohydraulic actuated motions and 2 passive wrist mobilizations. The dorsal radiocarpal, triquetrohamate, scaphocapitate, and scaphotrapeziotrapezoid ligaments were sectioned to replicate palmar midcarpal instability. Kinematic data for the scaphoid, lunate, and triquetrum were recorded before and after ligament sectioning and again after simulated triquetrohamate arthrodesis (TqHA) and radiolunate arthrodesis (RLA). RESULTS: Following ligament sectioning, the model we created for palmar midcarpal instability was characterized by significant increases in (1) lunate angular velocity, (2) lunate flexion-extension, and (3) dorsal/volar motion of the capitate during dorsal/volar mobilizations. Simulated TqHA caused significantly more scaphoid flexion and less extension during the wrist radioulnar deviation motion. It also increased the amount of lunate and triquetral extension during wrist flexion-extension. Simulated RLA significantly reduced scaphoid flexion during both wrist radioulnar deviation and flexion-extension. CONCLUSIONS: Both simulated arthrodeses eliminate wrist clunking and may be of value in treating palmar midcarpal instability. However, simulated RLA reduces proximal row motion whereas simulated TqHA alters how the proximal row moves. Long-term clinical studies are needed to determine if these changes are detrimental. CLINICAL RELEVANCE: Palmar midcarpal instability is poorly understood, with most treatments based on pathomechanical assumptions. This study provides information that clinicians can use to design better treatment strategies for this unsolved condition.

Scaphoid excision and midcarpal arthrodesis: the effect of triquetral excision--a biomechanical study.

PURPOSE: To evaluate the biomechanical alterations that occur after traditional scaphoid excision and midcarpal arthrodesis with and without excision of the triquetrum. The hypothesis of this study was that removal of the triquetrum increases the radiolunate contact pressure. METHODS: We cyclically moved 10 fresh cadaver wrists using a wrist joint motion simulator while measuring the contact pressures between the proximal carpal row and the distal radius and ulna using a dynamic pressure sensor. We acquired data in the intact wrist, after a midcarpal arthrodesis with the scaphoid excised, and then again with the triquetrum removed, which is also known as a capitolunate arthrodesis. RESULTS: The peak pressures in the radiolunate fossa significantly increased with either of the midcarpal arthrodeses compared with the intact wrist during each of the 3 dynamic wrist motions. In comparing the 2 midcarpal arthrodeses, the peak pressure in the ulnocarpal fossa significantly decreased after the triquetrum was removed during wrist radioulnar deviation and in the static ulnarly deviated position. After arthrodesis, we could identify no differences during any motion or static wrist position in the peak radiolunate pressures with or without the triquetrum. CONCLUSIONS: We found that scaphoid excision and 4-corner arthrodesis shifts loads to the radiolunate joint. Isolated capitolunate arthrodesis with excision of the scaphoid and triquetrum further alters carpal kinematics and loading patterns. CLINICAL RELEVANCE: These findings raise concern about routine excision of the triquetrum when performing a midcarpal arthrodesis.

Range of motion effects of distal pole scaphoid excision and triquetral excision after radioscapholunate fusion: a cadaver study.

PURPOSE: Radioscapholunate (RSL) fusion is an effective surgical procedure for the treatment of isolated radiocarpal arthritis. Although functional wrist motion is typically preserved through the midcarpal joint, many patients are still frustrated by postoperative limitations. The purpose of this study was to evaluate motion of cadaver wrists after simulated RSL fusion with excision of the distal pole of the scaphoid and the triquetrum. METHODS: Ten fresh-frozen cadaver upper extremities were mounted on a custom testing apparatus after isolation of the flexor carpi radialis, flexor carpi ulnaris, extensor carpi radialis longus, and extensor carpi ulnaris tendons. Sequential loading of these tendons resulted in flexion, extension, radial, and ulnar deviation. We subsequently measured range of motion with the use of digital photography. All specimens were tested in 4 states: intact (normal), RSL fusion (simulated), RSL fusion with distal scaphoid pole excision, and RSL fusion with distal scaphoid pole and triquetrum excision. The results were statistically analyzed using a repeated measures analysis of variance. RESULTS: Range of motion decreased to 39% to 46% of normal for flexion and extension and 65% to 71% of normal for radial and ulnar deviation after simulated RSL fusion. The addition of distal pole of scaphoid excision resulted in flexion and extension returning to 72% to 79% of normal, and radial and ulnar deviation returning to 84% to 89% of normal. Excision of the triquetrum further increased flexion and extension to 87% to 97% of normal, and radial and ulnar deviation to 119% to 137% of normal. CONCLUSIONS: The combination of triquetral and distal scaphoid pole excision after RSL fusion improves wrist motion to levels close to normal in the cadaver model.

Dorsal radiocarpal ligament capsulodesis for chronic dynamic lunotriquetral instability.

PURPOSE: Chronic lunotriquetral (LT) instability (persisting >3 months after injury) can be treated with a variety of surgical methods (LT fusion, ligament repair or reconstruction, or arthroscopic debridement), with varying degrees of success. We retrospectively evaluated the results of dorsal capsulodesis using the dorsal radiocarpal ligament in an attempt to reinforce the dorsal LT interosseous ligament in patients with chronic dynamic LT instability. METHODS: A total of 11 patients (mean age, 37 years) with persistent posttraumatic wrist pain and weakness were diagnosed with dynamic LT instability (positive LT ballotment test, disruption of Gilula's lines or volar intercalated segment instability deformity on stress radiography, arthroscopic findings of Geissler grade 3, or 4 LT tears). They were treated consecutively with dorsal capsulodesis. We used subjective and functional outcome measures to evaluate the results. RESULTS: The mean follow-up period was 31 months (range, 12-65 months). The postoperative visual analog pain score and Mayo wrist score were significantly improved compared with their preoperative values. The average grip strength increased by 5 kg, and the average range of wrist flexion was reduced by 3 degrees . CONCLUSIONS: In this small series, in the short term, dorsal radiocarpal ligament capsulodesis reduced pain and instability and improved function in patients with chronic dynamic LT instability. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Pisiformectomy in advanced pisotriquetral joint arthritis: A retrospective study of 12 wrists with a mean follow-up of 7.5 years.

Pisiformectomy is the gold standard treatment for pisotriquetral arthritis resistant to conservative treatment. We evaluated the long-term clinical and functional outcomes after pisiformectomy in resistant pisotriquetral arthritis cases. We retrospectively evaluated 11 patients (12 wrists), mean age of 59 years (49-69) treated by pisiformectomy using a standardized surgical technique. Pisiformectomy was performed for primary osteoarthritis in 10 cases, for post-traumatic osteoarthritis in 1 case and for pisotriquetral instability in 1 case. The clinical and functional evaluation was carried out by an independent examiner. Mean time to review was 90 months (63-151). Pain on a Visual Analog Scale (/10) decreased significantly to 1.1 from 6.8 preoperatively. Mean range of motion was 79° in flexion, 61.5° in extension, 18° in ulnar deviation and 36° in radial deviation. Mean grip strength of the operated wrist was 86% of the non-operated wrist. Functional scores significantly improved with a gain of 40 points for the QuickDASH and 53 points for the PRWE. Based on this long-term follow-up study, pisiformectomy seems to alleviate wrist pain and improve the quality of life in a low-demand population with pisotriquetral osteoarthritis resistant to conservative treatment. When compared to the pisotriquetral arthrodesis, pisiformectomy is easier to perform, allows quicker mobilization of the wrist and leads to good functional outcomes.

Triquetrohamate Impaction Syndrome: An Unrecognized Cause of Ulnar-Sided Wrist Pain; Its Presentation Further Defined.

BACKGROUND: The aim of this review was to further define the clinical condition triquetrohamate (TH) impaction syndrome (THIS), an entity underreported and missed often. Its presentation, physical findings, and treatment are presented. METHODS: Between 2009 and 2014, 18 patients were diagnosed with THIS. The age, sex, hand involved, activity responsible for symptoms, and defining characteristics were recorded. The physical findings, along with ancillary studies, were reviewed. Delay in diagnosis and misdiagnoses were assessed. Treatment, either conservative or surgical, is presented. Follow-up outcomes are presented. RESULTS: There were 15 male and 3 females, average age of 42 years. Two-handed sports such as golf and baseball accounted for more than 60% of the cases, and these cases were the only ones that involved the lead nondominant hand, pain predominantly at impact. Delay in diagnosis averaged greater than 7 months, with triangular fibrocartilage (TFCC) and extensor carpi ulnaris (ECU) accounting for more than 50% of misdiagnoses. Physical findings of note included pain over the TH joint, worse with passive dorsiflexion and ulnar deviation. Radiographic findings are described. Instillation of lidocaine with the wrist in radial deviation under fluoroscopic imaging with relief of pain helped to confirm the diagnosis. Conservative treatment was successful in 9 of 18 patients (50%), whereas in the remaining, surgical intervention allowed approximately 80% return to full activities without limitation. CONCLUSION: Triquetrohamate impaction syndrome remains an underreported and often unrecognized cause of ulnar-sided wrist pain. In this report, the largest series to date, its presentation, defining characteristics, and treatment options are further elucidated.

Ultrasound-Guided Steroid Injection of the Pisotriquetral Joint: A Multidisciplinary Effort.

From the perspective of a multidisciplinary team, the authors describe the first reported use of ultrasound guidance for steroid injection into the pisotriquetral joint to relieve wrist pain of a person with spinal cord injury undergoing acute inpatient rehabilitation. Musculoskeletal ultrasound guidance was used to improve the accuracy of a corticosteroid injection of the pisotriquetral joint and the basal thumb in a 70-year-old man with paraplegia experiencing multifocal degenerative wrist pain. There was no bleeding or bruising after the injections, and the patient reported complete pain resolution 1 wk after the injections, which continued for over 1 yr. A multidisciplinary team was key in diagnosis, selection of treatment, and evaluation of treatment effect. Corticosteroid injection of the pisotriquetral joint under ultrasound guidance can be used as a treatment modality for managing wrist pain stemming from that joint. Further investigation and studies evaluating the use of ultrasound versus other imaging modalities for injection of the wrist are indicated.

Latent pisotriquetral arthrosis unmasked following carpal tunnel release.

The causes of persistent wrist pain following carpal tunnel release include scar tenderness and pillar pain. The goal of this study was to evaluate latent pisotriquetral arthrosis as a source of ulnar-sided wrist pain following open carpal tunnel release. Seven hundred consecutive carpal tunnel releases were reviewed, looking for postoperative presentation of pisotriquetral arthrosis, as well as management and outcome. Fourteen patients with long-standing postoperative pain at the base of the hypothenar eminence had clinical and radiographic signs of pisotriquetral degenerative arthrosis, which conceivably had existed preoperatively and been unmasked thereafter. In 6 patients with persistent symptoms despite conservative measures, excision of pisiform was curative. Altered isometric stresses over the pisotriquetral articulation as a result of releasing the transverse ligament, which constitutes a major radial static stabilizer of this joint, seems to cause articular maltracking, and consequently aggravates a preexisting asymptomatic pisotriquetral arthrosis. Long-standing discomfort is characteristically associated with loss of grip strength and dexterity. Pisotriquetral dysfunction and arthrosis should always be considered in the differential diagnosis of persistent wrist pain following either open or endoscopic carpal tunnel release that does not respond to nonoperative measures. Clinical scrutiny, adequate clinical inspection, and radiographic evaluation readily establish the diagnosis. Conservative treatment includes immobilization, nonsteroidal anti-inflammatory drugs, and intra-articular injection of corticosteroids under fluoroscopic control. The corticosteroid injection combined with a local anesthetic also serves as a diagnostic test. Excision of the pisiform is indicated where conservative treatment has failed.

Pisotriquetral dysfunction following limited and total wrist arthrodesis.

PURPOSE: We report a series of pisotriquetral arthritis cases following wrist and intercarpal arthrodesis, offer an anatomic and biomechanical rationale, and introduce intraoperative considerations to avoid this potential complication. METHODS: Nine patients with pisotriquetral arthritis requiring pisiform excision following wrist and intercarpal arthrodesis were retrospectively evaluated at 2 institutions. Five paired cadaver wrists were tested for alterations in pressure and kinematics of the pisotriquetral joint following four-corner and total wrist fusions. RESULTS: Nine patients were successfully treated with pisiform excision for pisotriquetral arthritis following wrist and intercarpal fusions. Biomechanical cadaver testing demonstrated profound alterations in pisotriquetral kinematics and pressure changes in measured degrees of wrist position following wrist and intercarpal fusions. CONCLUSIONS: Patients undergoing four-corner and/or wrist arthrodesis should be assessed for pisotriquetral discomfort before surgery, including a physical examination and a 30 degrees supinated radiograph to look for degenerative changes. Attempts should be made intraoperatively to ensure that the proximal row is not fused in an extended position. After surgery, if discomfort develops and conservative treatment fails, then pisiform excision can successfully alleviate the pain.

Pisotriquetral arthrosis after triquetral malunion: a case report.

We report a patient with chronic ulnar palmar wrist pain caused by malunion after isolated fracture of the triquetrum. Intra-articular malunion of the triquetrum body resulted in posttraumatic pisotriquetral arthrosis. The diagnosis was made by magnetic resonance imaging, computed tomography, bone scintigraphy, and wrist arthroscopy 5 months after the injury. The patient's symptoms were relieved by excision of the pisiform.