Introduction The most common indications for a partial wrist fusion include scapholunate advanced collapse (SLAC) and scaphoid nonunion advanced collapse (SNAC) patterns. Other conditions include Kienböck disease, radiocarpal joint arthrosis secondary to a malunited distal radius fracture (DRF), and scaphotrapeziotrapezoidal (STT) osteoarthritis (OA). The pathophysiology of these conditions has been discussed in previous chapters. A variety of partial wrist fusions can be performed depending on the…

An arthroscopic resection of the distal scaphoid fragment can be regarded as a temporizing procedure for a chronic scaphoid waist nonunion or distal pole nonunion. It can relieve pain by alleviating the mechanical impingement between the hypertrophic distal pole and the radial styloid. It is especially indicated when the cartilage degeneration, osteophyte formation, and deformity are confined mainly to the radial styloid. It allows early wrist…

Pathophysiology An isolated tear of the scapholunate interosseous ligament (SLIL) changes carpal loading and kinematics even without demonstrable radiographic abnormalities. It can lead to attenuation of the secondary stabilizers and progressive dissociation and rotation of the scaphoid and the lunate. With axial loading over time, the capitate migrates proximally, further driving the scaphoid and lunate apart like a wedge. This results in midcarpal instability, loss of…

Relevant anatomy and etiology The dorsal wrist ganglion (DWG) is the most common cystic soft tissue tumor of the wrist. It typically originates from the dorsal portion of the scapholunate (SL) ligament at the junction of the dorsal capsular insertion, and it often expands dorsally between the third and fourth extensor compartments. It is filled with a viscous gel containing glucosamine, albumen, globulin, and hyaluronic acid.…

Relevant anatomy and etiology Dr. Robert Kienböck was a Viennese radiologist who described a series of patients presenting with radiographic signs of a collapsed lunate and attributed it to a traumatic disruption of the bone’s blood supply. Although more than 100 years have passed, the etiology of avascular necrosis (AVN) remains to be determined. After observing a negative ulnar variance in 74% of his patients with…

Pathophysiology Inflammatory arthritis is the most common situation where a synovectomy or biopsy may be indicated. Some causes of osteoarthritis may, however, also benefit from a synovectomy. A radiographic association between calcium pyrophosphate dihydrate crystal deposition disease (CPPD) and chronic scapholunate (SL) dissociation and scaphotrapezial (ST) osteoarthritis has been noted ( Fig. 15.1 ) but the question of cause and effect has not been completely settled.…

Pathomechanics Arthrofibrosis is due to an excessive fibrotic response following a prolonged inflammatory condition or a traumatic wrist injury or surgery, and it can lead to a progressive loss of joint motion. Wrist contractures can occur following any type of wrist injury, but are most prevalent following distal radius fractures (DRFs). Ganglion excision, carpal dislocation or fracture, previous wrist surgery, reflex sympathetic dystrophy, and prolonged immobilization…

Relevant anatomy and biomechanics A pure perilunate injury involves a dislocation of the carpus from the lunate, and constitutes a purely ligamentous injury to the wrist. Pure perilunate dislocations are considered lesser arc injuries because the traumatic force results in a circular disruption of ligaments close to the body of the lunate. Greater arc injuries occur when the force takes a path of greater circumference around…

Relevant biomechanics and natural history The development of osteoarthritis (OA) following displaced intraarticular fractures has been attributed to a variety of factors, including the initial trauma to cartilage, elevated contact stresses, and joint instability. Early cadaveric studies of simulated intraarticular fractures have demonstrated increased contact stresses using pressure-sensitive film inserted into the radiocarpal joint space. With a 1-mm scaphoid fossa depression, lunate fossa pressures increased in…

Distal radius fractures (DRF) occur as a consequence of trauma and they are one of the most common types of fractures. There is a bimodal distribution with high-energy fractures occurring in younger people, mostly males, and low-energy fractures occurring in older persons, mostly females. In 2006 there were 195.2 fractures per 100,000 people. At least $164,000,000 was spent on hospitalizations related to DRFs in 2000. Arthroscopy…

Relevant anatomy and biomechanics The scaphoid bone is the only carpal bone that bridges both the proximal and distal rows. As a result it is subjected to continuous shearing and bending forces. The scaphoid is tilted in 40 ± 3 degrees of palmar tilt degrees in the coronal plane with an intrascaphoid angle averaging and 32 ± 5 degrees in the sagittal plane from the central…

Relevant anatomy and biomechanics Many investigators have contributed to the understanding of midcarpal instability (MCI), which Lichtman consolidated into classifications ( Table 9.1 ). MCI represents several distinct clinical entities differing in the cause and direction of subluxation but sharing the common characteristic of abnormal force transmission at the midcarpal joint. The following discussion will center on intrinsic MCI. Extrinsic MCI due to a dorsally malunited…

Various authors have cast light on the importance of the dorsal radiocarpal ligament (DRCL) in maintaining carpal stability. Tears of the DRCL have been linked to the development of both volar and dorsal intercalated segmental instabilities and may be implicated in the development of midcarpal instability. Relevant anatomy and biomechanics The DRCL is an extracapsular ligament on the dorsum of the wrist. It originates on the…

Relevant anatomy and biomechanics The lunotriquetral interosseous ligament (LTIL) is C -shaped, similar to the scapholunate interosseous ligament (SLIL), and consists of true ligamentous dorsal and palmar subregions and an intervening fibrocartilaginous membranous portion. The palmar region is the thickest and strongest when tested to failure, and it is biomechanically the most important region in the transmission of load and strain from the triquetrum to the…

Relevant anatomy and biomechanics The scapholunate interosseous ligament (SLIL) is a C -shaped structure connecting the dorsal, proximal, and palmar surface between the scaphoid and the lunate, leaving the distal aspect of the joint bare. The SLIL has three subcomponents: a stronger dorsal component, a biomechanically unimportant membranous component, and a palmar component. The dorsal and palmar portions of the SLIL are true ligamentous structures. The…

Relevant anatomy and biomechanics Ulnar impaction can produce ulnar-sided wrist pain and can be related to ulnocarpal impaction (UCI) due to an ulnar-positive variance ( Fig. 5.1 ). Palmer et al. demonstrated that there was an inverse relationship between the thickness of the triangular fibrocartilage (TFC) and the ulnar variance: The more positive the ulnar variance, the thinner the TFC. Hara et al. found that the…

Relevant anatomy and biomechanics Triangular fibrocartilage complex anatomy The triangular fibrocartilage complex (TFCC) consists of the articular disc, the meniscus homologue, the palmar radioulnar ligament (PRUL) and dorsal radioulnar ligament (DRUL), the extensor carpi ulnaris subsheath (ECUS), the ulnar capsule, the ulnolunate ligament (ULL), and the ulnotriquetral (UT) ligament. , The PRUL and DRUL are the principal stabilizers of the distal radioulnar joint (DRUJ). As each…

Triangular fibrocartilage tears Relevant anatomy and biomechanics The triangular fibrocartilage complex (TFCC) has been well described. It consists of the articular disk, the meniscus homologue, the palmar radioulnar ligament (PRUL) and dorsal radioulnar ligaments (DRUL), the extensor carpi ulnaris subsheath (ECUS), the ulnar capsule, and the ulnolunate and ulnotriquetral ligaments. The PRUL and DRUL contain a superficial portion and a deep portion that are conjoined at…

Trapeziometacarpal joint portals Standard portals Menon initially presented his work on arthroscopy of the trapeziometacarpal joint (TMJ) as a meeting exhibit in 1994. He then published his experience with the arthroscopic management of trapeziometacarpal arthritis in 1996. He described two working portals: a volar portal just radial to the abductor pollicis longus (APL) tendon and a dorsal portal that is just ulnar to the APL along…

Introduction Since its inception, wrist arthroscopy has continued to evolve. The initial emphasis on viewing the wrist from the dorsal aspect arose from the relative lack of neurovascular structures and the familiarity of most surgeons with dorsal approaches to the radiocarpal joint. Anatomical studies have provided a better understanding of both the interosseous ligaments and carpal kinematics, which has led to the development of midcarpal arthroscopy…