The pisotriquetral joint: anatomic, biomechanical, and radiographic analysis

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.

Posttraumatic Arthrosis and Triquetral Nonunion Associated With Pisotriquetral Subluxation in Adolescent Female Softball Players

Impaction fracture subluxation of the pisotriquetral joint producing arthrosis and ulnar triquetral osteochondral nonunion is a cause for ulnar wrist pain in batting athletes. Two cases of adolescent female softball players managed successfully with pisiform and triquetral fragment excision are reported.

Our Disagreement on "Iceberg View" on the Ulnar Wrist and Clinical Implications

The diagnosis of ulnar-sided wrist symptoms concentrates on distal radioulnar joint and triquetral-hamate joint pathology. I consider this is only looking at the "tip of the iceberg" and ignoring other possible pathologies. In particular, this ignores the role of triquetrohamate and pisotriquetral pathologies. I outline our approaches to these pathologies noting the important ligamentous structures, the clinical presentations, the relevant investigations, and the surgical treatments and outcomes that I have found to be reliable. I would encourage hand surgeons to think more widely about ulnar-sided wrist symptoms, in particular triquetrohamate and pisotriquetral joint instabilities.

Isolated Carpal Dislocation of the Pisiform with Distal Radius Fracture in Two Adults: A Rare Entity

Background  Pisiform dislocations are an extremely rare injury. There are reports in the literature of isolated dislocations, but to our knowledge there are no reports of distal radius fractures with associated pisiform dislocations. Methods and Results  We present two cases of isolated pisiform dislocation and distal radius fracture in the adult population. Both patients were managed conservatively with closed reduction in both the distal radius and pisiform, and subsequently achieved good pain relief and progressive return of wrist function. Conclusion  For adult patients with distal radius fractures and an associated pisiform dislocation, successful closed reduction and immobilization can result in symptomatic improvement and return of function.

Locked Wrist: A Case Report and Literature Review on Pisotriquetral Loose Bodies

Background  Pisotriquetral (PT) loose bodies have been described in the literature only a few times as case reports. While PT pathology remains the differential for ulnar-sided wrist pain, it can often be difficult to diagnose, as symptoms can be variable and radiographic imaging may be negative for any findings. Case Description  A 24-year-old major league baseball player presented with pain and locking of his wrist during follow through of his bat swing. Plain radiographic imaging, as well as computed tomography (CT) imaging, was negative for any pathology. Dynamic magnetic resonance imaging (MRI) demonstrated a loose body which entered the PT joint when the wrist was moved into a flexed position. This caused entrapment of the loose body and locking of the wrist. Literature Review  A total of 17 reported patients in the literature have been diagnosed with a PT loose body. The clinical examination findings, radiographic findings, and surgical findings are reviewed. Case Relevance  PT loose bodies can present a challenging clinical picture to diagnose. The purpose of this case report is to review the appropriate clinical workup, including common examination findings and advanced imaging techniques, to help the clinician with the diagnosis.

Long-Term Results of Pisiformectomy in a Cohort of 57 Patients

Background  Excision of the pisiform is an infrequently used option for pisotriquetral joint dysfunction when nonoperative treatment is ineffective. This study reviews the patient-reported outcomes of patients treated with pisiformectomy, and furthermore focuses on the complications and the need for and time to revision procedure. Materials and Methods  Medical records of 57 patients were manually reviewed and assessed for complications, rate of unplanned reoperations, and type of reoperations. Thirty-seven patients (65%) completed patient-rated outcomes surveys at a median of 10 years after their procedure. Results  The complication rate was 13% ( n  = 7). Ulnar nerve symptoms were noted in three patients. No reoperations were performed after the pisiform excision. Out of the 16 patients who had preoperative symptoms of ulnar nerve compression at the wrist, 10 patients reported that their symptoms had completely resolved after the surgery. The median Quick Disability of Arm, Shoulder and Hand (QuickDASH) score after surgery was 4.5 (2.3-16), median score for pain 0 (interquartile range [IQR]: 0-2), and median score for overall satisfaction 10 (IQR: 8-10). Conclusions  Pisiformectomy is a surgery used sparingly in cases with refractory pain associated with arthrosis of the pisotriquetral joint or enthesopathy of the flexor carpi ulnaris/pisiform interface. When utilized in this fashion, patients report limited disability on patient-rated outcome measures, low pain scores, and high satisfaction at mid- to late follow-up.

Volar Dislocation of the Fourth and Fifth Carpometacarpal Joint Associated with Hamate Hook Fracture: A Case Report and Literature Review

We report a case of volar fourth and fifth carpometacarpal (CMC) joint dislocation complicated by a hamate hook fracture. The CMC joint was reduced in a closed fashion and temporally fixed with Kirschner wires. Using intraoperative computed tomography, the displaced fracture of the hamate hook was reduced by open reduction and internal fixation and fixed with a screw. We suggest that this rare injury was caused by the over contraction of the flexor carpi ulnaris and avulsion force from the ligamentous structure around the pisiform, hamate, and metacarpal bones.

Anatomy of the Volar Retinacular Elements of the Hand: A Unified Nomenclature

Many investigators have described the anatomy of the volar retinacular structures of the hand over the last 60 years. As a result, multiple terms have been assigned to 1 anatomical structure and 1 name designated to more than 1 structure. Our purpose is to review the detailed anatomy and key components of the volar retinacular elements of the hand, their etymology, and their most recent descriptions. The objective also is to organize these structures into systems, which can be helpful for learners to assimilate into a practical anatomical guide. Lastly, the goal is to create a common nomenclature for identifying the volar retinacular structures of the hand in order to facilitate clear communication about them across languages.

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.

Suture Fixation Using Polyblend Polyethylene Sutures With Hydroxyapatite Block for an Intra-articular Depression Fracture of the Pisiform Bone

Few cases in which open reduction and internal fixation was performed for displaced pisiform fractures have been reported. We present a new surgical technique for the treatment of depressed intra-articular pisiform fractures. First, the depressed fragment was reduced by pushing the bone tamp. Then, the fracture void resulting from the reduction of the depressed fragment was filled with a shaped hydroxyapatite block. Finally, the fragments were sutured using braided polyblend polyethylene sutures. The postoperative radiography could achieve a well-reduced articular facet, and this procedure had a good clinical outcome.

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.

Assessment of pisotriquetral misalignment with magnetic resonance imaging: Is it associated with trauma?

OBJECTIVE

Our objective was to determine whether there is an association between pisotriquetral (PT) malalignment and acute distal radius fracture by using magnetic resonance imaging (MRI).

METHODS

We evaluated 138 patients who underwent 3-T MRI of the wrists. Group A comprised 85 patients with acute distal radius fracture, and group B comprised 53 patients without trauma. PT interval and angle and pisiform excursion were measured on oblique axial and sagittal multiplanar reformats. The presence of abnormalities in the flexor carpi ulnaris tendon (FCU), pisometacarpal ligament (PML), and pisohamate ligament (PHL) were evaluated.

RESULTS

PT interval was wider in group A on both the axial and sagittal planes (P < 0.001). Axial PT angle opened more radially in group A (P < 0.001), and the absolute value of the sagittal PT angle in group A was wider than that in group B (P = 0.006). Abnormalities in FCU, PML, and PHL were more frequently observed in group A (P < 0.001). On multiple linear regression, distal radius fracture remained significant after adjusting for the patient's age and PT osteoarthritis.

CONCLUSIONS

Acute distal radius fracture can affect normal alignment of the PT joint, resulting in associated injuries to the primary PT joint stabilizers.

KEY POINTS

• Acute distal radius fracture is associated with malalignment of PT joints. • Acute distal radius fracture is associated with abnormalities of PT stabilizers. • PT joint alignment can be evaluated with MRI with 3D sequences. • Wrist MRI is useful for evaluating primary PT stabilizer injuries.

The Prevalence of Pisotriquetral Arthritis in the Setting of Scapholunate Advanced Collapse

Background Previous authors have reported pisotriquetral pain and subsequent pisiform excision following partial or total wrist fusion in patients with scapholunate advanced collapse (SLAC). Prior studies have not considered the potential role of SLAC biomechanics on pisotriquetral osteoarthritis (PT OA) development preoperatively. Purpose To determine the prevalence and severity of PT OA in patients with SLAC as compared with a control population. Patients and Methods Magnetic resonance imaging (MRI) studies of 24 patients with SLAC wrist and 24 sex- and age-matched control patients were analyzed. Patients with SLAC wrist were selected from a database of all wrist MRI studies performed at our institution from 2006 to 2015, excluding those with inflammatory arthritis, chondrocalcinosis, and incomplete or atraumatic scapholunate interosseous ligament rupture. Control patients underwent MRI for nonarthritic clinical indications and were chosen in an age- and sex-matched fashion. Patients undergoing MRI for triangular fibrocartilage complex injury, extensor carpi ulnaris tendinopathy, or ulnar-sided wrist pain were excluded from the control cohort. MRI grading of arthritic change at the pisotriquetral joint was assessed by a blinded musculoskeletal radiologist according to a four-category scale, with grade 4 indicating the greatest arthritic severity. Results The prevalence of PT OA in the control cohort was found to be 37.5% compared with 41.7% in the SLAC cohort. The prevalence of greatest arthritic severity (grade 4) at the pisotriquetral joint was found to be 4.2% in the control cohort, compared with 16.7% in the SLAC cohort. Conclusion We conclude that the overall prevalence of chondral wear at the pisotriquetral joint in SLAC wrist does not differ significantly from that found in control populations. We did identify a fourfold (but not statistically significant) increased prevalence of end-stage arthritis in patients with SLAC. Given reports of symptomatic PT OA developed following four-corner arthrodesis, we recommend preoperative vigilance for pisotriquetral pain in patients with SLAC arthritis. Level of Evidence Prognostic level III.

Uncommon carpal fractures

Fractures of the hand are frequently encountered with injuries to the phalanges and metacarpals comprising the vast majority. Fractures of the carpal bones excluding the scaphoid, however, are fairly uncommon. Despite the rarity of fractures of the remaining seven carpal bones, they can cause a disproportionate amount of morbidity from missed diagnosis due to their subtlety as well as their frequent association with significant ligamentous disruption or even other carpal bone fractures. Delayed diagnosis can result in inadequate fracture care, which places the wrist at risk of disabling sequelae. This review focuses on the current concepts of pathophysiology, diagnosis, and treatment of carpal fractures other than the scaphoid.

The pisiform growth plate is lost in humans and supports a role for Hox in growth plate formation

The human pisiform is a small, nodular, although functionally significant, bone of the wrist. In most other mammals, including apes and Australopithecus afarensis, pisiforms are elongate. An underappreciated fact is that the typical mammalian pisiform forms from two ossification centers. We hypothesize that: (i) the presence of a secondary ossification center in mammalian pisiforms indicates the existence of a growth plate; and (ii) human pisiform reduction results from growth plate loss. To address these hypotheses, we surveyed African ape pisiform ossification and confirmed the presence of a late-forming secondary ossification center in chimpanzees and gorillas. Identification of the initial ossification center occurs substantially earlier in apes relative to humans, raising questions concerning the homology of the human pisiform and the two mammalian ossification centers. Second, we conducted histological and immunohistochemical analyses of pisiform ossification in mice. We confirm the presence of two ossification centers separated by organized columnar and hypertrophic chondrocyte zones. Flattened chondrocytes were highly mitotic, indicating the presence of a growth plate. Hox genes have been proposed to play a fundamental role in growth plate patterning. The existence of a pisiform growth plate presents an interesting test case for the association between Hox expression and growth plate formation, and could explain the severe effects on the pisiform observed in Hoxa11 and Hoxd11 knockout mice. Consistent with this hypothesis, we show that Hoxd11 is expressed adjacent to the pisiform in late-stage embryonic mouse limbs supporting a role for Hox genes in growth plate specification. This raises questions concerning the mechanisms regulating Hox expression in the developing carpus.

[Is there pisotriquetral instability after carpal tunnel release? Retrospective study of 55 cases]

The aim of this study was to determine if pisotriquetral instability is present after neurolysis of the median nerve in the wrist. Fifty-five patients who underwent carpal tunnel release between December 2005 and March 2009 were included in this retrospective study. The surgical procedure consisted of cutting the transverse carpal ligament under local anesthesia through an anterior approach. Instability was evaluated clinically and radiologically by measuring the pisometacarpal angle. The mean patient age was 61years and the mean follow-up 42months. Only 9% of patients complained of pain on the ulnar side of wrist. The pisometacarpal angle in all the operated wrists was the same as in the non-operated wrists. Our findings suggest there is no pisotriquetral instability after median nerve neurolysis.

The effect of pisiform excision on wrist function

PURPOSE

To investigate the effect of pisiform excision on wrist function compared with age- and sex-matched control subjects.

METHODS

The authors evaluated the charts of 11 consecutive patients who had undergone pisiform excision. Nine of these patients could be included and clinically examined, and results were compared with 9 matched controls. Measurements included range of motion, strength measurements, neurological examination, and questionnaires.

RESULTS

Extension in the operated wrist was reduced in patients compared with controls. The Disabilities of the Arm, Shoulder, and Hand and Michigan Hand Outcomes Questionnaires were significantly different between patients and controls. All other entities were equal between groups. Subjectively, patients experienced impairments in function of the operated wrist, but these could not be identified objectively.

CONCLUSIONS

Although great care must be taken in handling the surrounding soft tissue, pisiform excision is a well-tolerated, safe treatment for pain in the pisotriquetral joint resulting from arthrosis and not controlled by nonsurgical means.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic III.

Pisiform excision for pisotriquetral instability and arthritis

PURPOSE

To evaluate wrist strength and kinematics after pisiform excision and preservation of its soft tissue confluence for pisotriquetral instability and arthritis.

METHODS

We evaluated 12 patients, (14 wrists) subjectively and objectively an average of 7.5 years after pisiform excision. Three additional patients were interviewed by phone. Subjective evaluation included inquiry about pain and satisfaction with the treatment. Objective testing included measuring wrist flexion and extension range of motion, grip strength, and static and dynamic flexion and ulnar deviation strengths of the operative hand compared with the nonsurgical normal hand. Four patients had concomitant ulnar nerve decompression at the wrist.

RESULTS

All patients were satisfied with the outcome. Wrist flexion averaged 99% and wrist extension averaged 95% of the nonsurgical hand. Mean grip strength of the operative hand was 90% of the nonsurgical hand. Mean static flexion strength of the operative hand was 94% of the nonsurgical hand, whereas mean dynamic flexion strength was 113%. Mean static ulnar deviation strength of the operative hand was 87% of the nonsurgical hand. The mean dynamic ulnar deviation strength of the operative hand was 103% of the nonsurgical hand.

CONCLUSIONS

Soft tissue confluence-preserving pisiform excision relieved pain and retained wrist motion and static and dynamic strength. Associated ulnar nerve compression was a confounding factor that may have affected outcomes.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

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.

Comparison of clinical results after pisiformectomy in patients with rheumatic versus posttraumatic osteoarthritis

Pisotriquetral osteoarthritis is important to consider in the differential diagnosis of chronic ulnar-sided wrist pain. It can develop following traumatic injury to the pisiform or in rheumatic diseases, such as rheumatoid arthritis or psoriatic arthritis. It has been shown that pisiformectomy can relieve symptoms in cases that have not responded to nonoperative treatment, and the excision does not compromise the function or strength of the wrist. Most studies focus on posttraumatic causes of pisotriquetral osteoarthritis. In the current study, rheumatic causes are also considered and the outcomes are compared. This retrospective study included 35 patients who underwent pisiformectomy for pisotriquetral osteoarthritis. All patients underwent a thorough diagnostic evaluation to exclude other etiologies for ulnar-sided wrist pain. Radiological examinations including posteroanterior and lateral views of the wrist and a tangential view of the pisotriquetral joint were analyzed. All patients had excellent or very good results after pisiformectomy, with a significant reduction in pain. No significant difference was found in the outcomes for patients with rheumatic vs posttraumatic osteoarthritis. Patients with rheumatic causes of pisotriquetral osteoarthritis can be successfully treated with pisiformectomy. With respect to idiopathic causes, these patients need a longer postoperative period to gain full pain relief. It is important to consider the possibility of pisotriquetral osteoarthritis after excluding other diagnoses in patients with rheumatic osteoarthritis.

Fractures of the hamate and pisiform bones

Osseous injuries to the ulnar aspect of the carpus are increasing in frequency because of greater participation in sporting activities. Hamate body fractures are subdivided into coronal, sagittal oblique, proximal pole, and medial tuberosity fractures. Successful treatment of coronal fractures requires identification and treatment of associated disruption or instability of the ulnar 2 carpometacarpal joints. Displaced hamate hook fractures are optimally treated with early excision to avoid sequelae such as flexor tendon and nerve injury, and to allow early return to activity. Undisplaced pisiform fractures are managed nonoperatively, whereas displaced fractures and nonunions are treated by simple excision.

Anatomical study of the pisotriquetral joint ligaments using ultrasonography

OBJECTIVE

The aim of this study was to demonstrate that ultrasonography may allow a precise assessment of the primary stabilizers of pisotriquetral joint (pisohamate, pisometacarpal, and ulnar pisotriquetral ligaments).

METHODS AND MATERIALS

This study was initially undertaken in eight cadavers. Metal markers were placed in the ligaments using ultrasonographic guidance, followed by the dissection of the wrists. High-resolution ultrasonography was then performed in 15 volunteers (30 wrists) for the analysis of the presence, appearance, and thickness of the ligaments.

RESULTS

At dissection, the metal markers were located in the ligaments or immediately adjacent to them, confirming that they were correctly depicted using ultrasonography. The three ligaments could also be identified in each volunteer. The optimal positioning of the probe and the dynamic maneuvers of the wrist allowing the strain of these ligaments could be defined. No significant changes in the appearance and thickness of the ligaments could be observed.

CONCLUSIONS

The three ligaments stabilizing the pisotriquetral joint can be identified using ultrasonography. Further studies are now required to know whether this knowledge may be useful in the assessment of pain involving the ulnar part of the wrist.

Pisotriquetral arthrodesis for pisotriquetral instability: case report

A 22-year-old professional downhill mountain bike rider developed increasing posttraumatic pisotriquetral instability. To preserve full function of the pisiform bone, we performed pisotriquetral arthrodesis using a Herbert screw. Ten months after the splint was removed, the patient was free of symptoms and returned to professional downhill mountain biking without limitations. This uncommon method seems to be a feasible treatment strategy and can be recommended in high-demand patients.

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.

Anatomy of the ulnar tunnel and the influence of wrist motion on its morphology

PURPOSE

To examine the anatomy of the ulnar tunnel, with emphasis on the pisohamate arcade and pisohamate hiatus, and study the influence of wrist kinematics on the morphology of these structures.

METHODS

Ten fresh-frozen cadaveric hands were dissected. The dimensions and relationships of the ulnar tunnel, pisohamate arcade, and pisohamate hiatus were recorded. The effect of 4 wrist positions on these dimensions and relationships was investigated.

RESULTS

The ulnar tunnel has 3 compartments--proximal, middle, and distal relative to the pisiform-with variable morphologies, dimensions, and boundaries. In wrist neutral position, the length of the ulnar tunnel was 45 mm (range, 42 to 51 mm). The middle compartment was found to be the narrowest; the proximal, the widest, averaging 5.0 mm; and the pisohamate hiatus that separates the middle and distal compartments, highly dynamic. The length of the pisohamate arcade was 21.5 mm (range, 18.0 to 26.0 mm), and the length and width of the pisohamate hiatus were 11.0 mm (range, 9.8-11.5 mm) and 6.0 mm (range, 5.3 to 7.2 mm), respectively. During wrist extension, the ulnar nerve was under tension. Wrist flexion was the position that caused the most change in ulnar tunnel and pisohamate arcade and hiatus anatomy, causing the width of the proximal compartment to increase from 5.0 to 10.0 mm. During this motion, the shape of the pisohamate arcade changed from a C shape to linear, and the length increased to 24.5 mm (range, 19.3 to 28.5 mm). The pisohamate hiatus narrowed, its width decreased to 1.5 mm, and the deep branch of the ulnar nerve was somewhat compressed.

CONCLUSIONS

The ulnar tunnel is a dynamic space with dimensions and relationships that are influenced by wrist motion. During ulnar tunnel surgery, all 3 compartments of the ulnar tunnel should be explored and decompressed, including the pisohamate hiatus, by releasing the pisohamate arcade.

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.

Osteoarthritis of the wrist

Osteoarthritis of the wrist is one of the most common conditions encountered by hand surgeons. It may result from a nonunited or malunited fracture of the scaphoid or distal radius; disruption of the intercarpal, radiocarpal, radioulnar, or ulnocarpal ligaments; avascular necrosis of the carpus; or a developmental abnormality. Whatever the cause, subsequent abnormal joint loading produces a spectrum of symptoms, from mild swelling to considerable pain and limitations of motion as the involved joints degenerate. A meticulous clinical and radiographic evaluation is required so that the pain-generating articulation(s) can be identified and eliminated. This article reviews common causes of wrist osteoarthritis and their surgical treatment alternatives.

Pisiform ligament complex syndrome and pisotriquetral arthrosis

PLC syndrome is a spectrum that encompasses PLC instability and ends with PTA. Early recognition and treatment of PLC instability may disrupt its progression to PTA. The pisiform tracking test is a provocative maneuver that aids in diagnosing PLC syndrome. Pisiformectomy with preservation of the soft tissue confluence remains the treatment of choice for severe PLC syndrome that does not respond to nonoperative treatment.

Avulsion fracture of the hamulus from clay gunshot sport: a case report

We report a case of hamulus (hook of hamate) fracture nonunion and secondary flexor digitorum profundus tendon rupture caused by repetitive wrist hyperextension sustained during clay shotgun shooting. The hyperextension caused avulsion of the hamulus by the pisohamate ligament. The hamulus was excised and a flexor digitorum profundus tendon transfer of the ring to small finger side to side was performed with satisfactory outcome.