Arthroscopic staging

Arthroscopic Stage I patients are characterized by diffuse synovitis, but with minimal, if any, articular cartilage loss (Fig. 1). Ligamentous laxity, particularly the entire volar capsule, is a frequent finding. This presentation is relatively uncommon, because most patients present late, having suffered with symptoms for a long period; or are referred at

Fig. 1. Arthroscopic Stage I findings demonstrate synovitis around the volar oblique ligament, with intact articular cartilage on the trapezium.

a delayed time once conservative means have been exhausted. These patients undergo synovectomy, both mechanical and by radiofrequency, with occasional shrinkage capsulorraphy performed, depending on findings. The joint is then protected in a thumb spica cast from 1 to 4 weeks, depending on the extent of capsular laxity. More unstable joints required longer immobilization to achieve joint stability and presumably slow the progression of articular cartilage degeneration.

Arthroscopic Stage II patients are characterized by focal wear of the articular surface on the central to dorsal aspect of the trapezium. In the author's mind, this represents an irreversible process, and requires a joint-modifying procedure to alter the vector force across the joint. After synovectomy, debridement, and occasional loose body removal, the joint is reassessed to determine the extent of instability and capsular attenuation (Fig. 2). A shrinkage thermal capsulorraphy is performed in many of the cases, with chondro-plasty frequently performed to anneal the cartilage borders (Fig. 3). The arthroscope is then removed and the ulnar portal extended distally to expose the metacarpal base. A dorsoradial closing wedge osteotomy, similar to Wilson's original technique [21], is then performed to place the thumb in a more extended and abducted position. This is to minimize the tendency for metacarpal subluxation and to change the contact points of worn articular cartilage. The osteotomy is protected by a single oblique Kirschner wire that is also placed across the first CMC joint in a reduced position.

This allows for healing of the osteotomy in the correct position, and also a correction of the i I I

Fig. 2. Arthroscopic Stage II typical findings include small area of articular cartilage loss on deep aspect of metacarpal at insertion of volar beak ligament and central, focal loss of trapezial joint surface. This stage often demonstrates loose bodies as seen here during extrication.

metacarpal subluxation often seen in this stage. A thumb spica cast protects this during healing, and the wire is removed at 5 weeks postoperative. Only arthroscopy can determine the optimal indications for this osteotomy, which has demonstrated good results in the past, and in a more recent paper by Tomaino [22]. Late follow up on the author's patients has demonstrated that the metacarpal remains "centralized," and it is unclear if the capsular shrinkage plays a role versus the alteration of biomechanics by the use of osteotomy (Figs. 4 and 5).

Arthroscopic Stage III is characterized by much more diffuse trapezial articular cartilage

Fig. 3. Shrinkage capsulorraphy being performed on deep aspect of capsule noted to be attenuated because of chronic deposition of corticosteroid.
Fig. 4. Preoperative radiograph in middle-aged woman demonstrating metacarpal base subluxation free of os-teophytes. Arthroscopy demonstrated focal trapezial wear indicative of Badia arthroscopic Stage II arthritis. Patient indicated for osteotomy of metacarpal base.

loss (Fig. 6). The metacarpal base can also be devoid of cartilage to varying degrees. Arthroscopic findings indicate that this is not a joint worth preserving, and a simple debridement or even accompanying osteotomy will not give a good long-term

Fig. 5. One-year postoperative radiograph after metacarpal osteotomy (and pin removal) demonstrating the persistent "centralization" of the metacarpal on the trapezium. This changes the joint contact points that may have led to progression of arthrosis and pain.

Fig. 5. One-year postoperative radiograph after metacarpal osteotomy (and pin removal) demonstrating the persistent "centralization" of the metacarpal on the trapezium. This changes the joint contact points that may have led to progression of arthrosis and pain.

Fig. 6. Arthroscopic Stage III findings include diffuse articular cartilage loss on both trapezium and metacarpal base. Chronic inflammation leads to capsular fraying evident here.

result in this case. An arthroscopic hemitrapeziec-tomy is then performed by burring away the remaining articular cartilage and also removing subchondral bone down to a bleeding surface. This serves to not only increase the joint space, but to allow for bleeding that will form an organized thrombus, which will adhere to an interposed tendon graft. This graft, either palmaris longus or the volar slip of APL, is inserted via a portal, similar to the technique as proposed by Menon [2] (Fig. 7). A thumb spica cast in an abducted position is then maintained for 4 weeks, followed by hand therapy to focus on pinch strengthening. Stage III can also be treated by a traditional open excisional arthroplasty [23-26], arthrodesis [18], or total joint replacement [27], depending on surgeon preference.

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Arthritis Joint Pain

Arthritis Joint Pain

Arthritis is a general term which is commonly associated with a number of painful conditions affecting the joints and bones. The term arthritis literally translates to joint inflammation.

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