A 34-year-old right-hand-dominant warehouse manager for the county elections department was referred for persisting ulnar-sided wrist pain of his nondominant hand. Some months prior, he had undergone wrist arthroscopy by a general orthopaedist due to presumed triangular fibrocartilage complex (TFCC) pathology. At the time of initial injury, he noted immediate pain after a hyperextension injury where he then presented to an occupational health center and he was automatically referred for therapy. After seven sessions with no improvement, he was referred to the general orthopaedist who performed arthroscopy of the wrist, apparently the radiocarpal joint only, and he reported performing simple debridement of the TFCC. There was no specification as to whether this was a peripheral or central lesion. Postoperatively, he was placed in a short arm splint for only 1 week, allowing protosupination, and then he began therapy again. The patient quickly noted that he had no improvement and requested consultation with a hand specialist via workers’ compensation.
The patient presents with persistent ulnar-sided wrist pain that is aggravated even by simple daily activity including driving. His job is not very manual and he had continued to work for the most part in a supervisory capacity. At physical examination, there was no visible swelling or deformity, but there was pain with extreme ulnar deviation and some discomfort with passive translation of the distal radioulnar joint although there was no clunking. There was also minimal pain with hypersupination of the wrist and there was a negative lunotriquetral (LT) shuck test and no tenderness over the extensor carpi ulnaris (ECU). Grip strength on the left was diminished to 95 lb compared to 125 lb on the right dominant side. Plain X-rays demonstrated no osseous abnormalities and no carpal stability patterns. He demonstrated ulnar neutral variance. Due to persistent pain after wrist arthroscopy, an MRI was performed that showed peripheral fraying of the TFCC articular disk but no complete detachment of the structure, and a normal LT ligament was specifically mentioned. There were no other relevant findings in this 1.5-T closed MRI read by an experienced MSK (musculoskeletal) radiologist.
This patient is suffering from persistent pain in the ulnar-sided wrist, often termed the “low back of the wrist,” after a relatively minor hyperextension injury of the wrist. It is important to understand the vast differential diagnosis that is present here with careful clinical assessment, but often requiring detailed wrist arthroscopic assessment to confirm, elucidate, and provide definitive treatment during this vital procedure.
This patient already underwent wrist arthroscopy, but by a less experienced clinician who practices general orthopaedics. It is important to read the op note and then confirm by that review and visual assessment of the wrist dorsum that a midcarpal arthroscopy was not performed. Persistent ulnar wrist pain after arthroscopic debridement can have many causes. For starters, one must determine if a simple debridement sufficed, and many times this friable tissue can quickly degenerate, leading to recurrent secondary synovitis. Furthermore, a peripheral repair may actually be needed and this would require an ample period of immobilization, usually in supination. Conversely, a central degenerative-type tear (Palmer type IIa) needs to be stabilized and this is best done with radiofrequency shrinkage. This assumes that the TFCC pathology is the primary cause for the ulnar-sided wrist pain. Other causes of pain need to be ruled out.
Much of the ulnar wrist pain differential can be ruled out by clinical examination, starting by simple palpation. Starting by range of motion assessment, the fact that full supination was possible with minimal discomfort often rules out a significant peripheral TFCC tear. Pain with radial and ulnar deviation can be less specific. Palpating particular structures with a clear understanding of anatomy is vital. This patient had no tenderness along the course of the ECU and there were no signs of subluxation, as might be seen with a sixth compartment subsheath tear. These issues can largely be ruled out by ultrasound assessment, something the author now routinely performs in the office environment. Short-axis ultrasound assessment of the ECU will show if significant fluid around the tendon is present and dynamic examination will show if there is tendon subluxation out of the dorsoulnar groove.
Palpation around the carpus tends to be less specific, but certainly a significant intercarpal ligament tear will usually demonstrate point-specific tenderness to firm palpation. Provocative maneuvers, such as the LT shuck test and Watson’s test, are typically positive if carpal instability is present. However, smaller tears can cause pain with little biomechanical consequence other than weakness in grip and pain with extremes of motion. These truly require arthroscopic assessment, and via the midcarpal portals, to elucidate symptomatic grade II and III tears (Geissler’s criteria). A negative MRI in this clinical instance is neither surprising nor particularly helpful in the overall assessment of this patient with persistent ulnar-sided wrist pain.
This patient requires a stepwise, detailed arthroscopic assessment of the wrist. Further diagnostic studies might only serve to confuse and certainly do not address the patient’s clinical problem, which is clearly persistent pain.
Arthroscopy of the wrist must almost always include both radiocarpal and midcarpal joint assessment from dorsal portals. Distal radioulnar joint assessment has more limited indications but certainly may prove valuable if the radiocarpal view of the ulnar compartment sheds no light on the etiology of pain, for example, an Atzei class 3 lesion of type IB TFCC tear of the articular disk insertion. Volar portals are occasionally used for more in-depth assessment of the dorsal extrinsic ligaments or when a more difficult arthroscopic arthrolysis is performed.
Midcarpal arthroscopy will be crucial to assess for intercarpal ligament tears, namely, lesions causing dynamic carpal instability. A high index of suspicion for LT tear in this patient must be maintained as he already had a failed simple wrist arthroscopy. Although his examination appeared more focal and ulnar directed, we must ensure that a floating lunate lesion (or Herzberg type 0 perilunate injuries, not dislocated (PLIND) lesion) is not present, where scapholunate disruption is concomitantly present with the LT pathology. This can be easily determined and generally requires aggressive ligament debridement, coupled with pin fixation, as will be discussed.
• Extrinsic causes of ulnar wrist pain ruled out.
• Radiocarpal arthroscopy assesses previous procedure/current pathology.
• Midcarpal arthroscopy determines if carpal instability present.
• Post-op immobilization (type + time period) depends on procedure performed.
• Wrist rehabilitation critical to regain motion, followed by strength.
The patient was placed in the supine position with the upper arm held down with a Velcro strap over the upper arm tourniquet. Simple wrist block anesthesia was placed once slight intravenous (IV) sedation was induced. The wrist was distracted via the Chinese finger traps on the index and middle fingers, which we used to provide 10 lb of traction with an arm holder that would allow easy introduction of fluoroscopy into the operating room field. A traditional wrist tower is never utilized.
With the wrist in pronation and the surgeon sitting at the head of bed, the joint is insufflated just distal to Lister’s tubercle using an 18-G needle and several milliliters of a local anesthetic mixture of lidocaine/Marcaine. The 2.7-mm 30-degree arthroscope is introduced into the 3–4 working portal created via a small transverse incision. Cursory, but systematic examination, of the radiocarpal joint is made by beginning on the radial side and progressing ulnarward. The 2.9-mm full radius shaver is inserted in the 6R portal, which allows for immediate synovectomy (▶Fig. 81.1a), necessary to identify the anatomy and assess for any abnormalities and the primary pathology. This thorough synovectomy is also vital for post-op pain relief, but the offending injury causing this process must now be identified (▶Fig. 81.1b). Looking toward the ulnocarpal compartment, minor adhesions and subtle changes in the coloration of the peripheral TFCC are noted once the proliferative synovium is cleared (▶Fig. 81.1c). This represents scar from prior debridement but appears to have little clinical relevance as no detachment is noted, there is no loss of trampoline effect, and the lift-off test is negative, all of which are determined by palpation with a small hook probe. To stabilize some of the frayed dorsal capsule and articular disk capsular insertion, a 2.5-mm bipolar radiofrequency shrinkage probe is then inserted via 6R and is utilized with a “striping technique.” Essentially the relevant soft tissues are touched with the probe in horizontal, parallel, but spaced stripes so that the intervening tissue perfusion is unaltered. This allows for capsular healing and minimizing redundancy and recurrent synovitis. The SL ligament had been clearly visualized and unremarkable, but the LT ligament is poorly seen via the radiocarpal portals. Regardless, the volar component is biomechanically more critical, and this would be assessed from the midcarpal joint.
The syringe/needle is also utilized to help dilate the midcarpal joint via the radial midcarpal portal, just distal and slightly more ulnar than the 3–4 portal. After opening the portal with a straight, small mosquito clamp, the arthroscope is introduced. Similar systematic assessment is performed in the midcarpal joint where the SL ligament, articular surfaces of scaphoid, lunate, and capitate are all examined. Almost immediately, it was noted that there is a step off and even mild diastasis of the LT interval (▶Fig. 81.2a). The ulnar midcarpal portal is created by localization with an 18-G needle, and the full radius shaver is now inserted. Thorough synovectomy is performed, so this interval and the dorsoulnar midcarpal capsule can be better visualized. The hook probe is soon inserted and the gross motion, much more than normally deemed acceptable, confirms the presence of an LT ligament tear with dynamic instability. The probe is easily inserted in the interval and can be rotated 90 degrees, constituting a grade III tear as per the Geissler staging of intercarpal ligament tears (▶Fig. 81.2b). In order to stabilize and reverse this motion, we will create scar by aggressively debriding the intercarpal LT interval with particular attention to the volar aspect where the most critical portion of LT stability is found. Similar limited shrinkage is performed to the dorsal capsule and at this point the arthroscope is retired. To truly generate a new surrogate ligament, we must minimize motion at the interval. Fluoroscopy is now brought in via a sagittal plane so that we can visualize the LT interval, initially by the posteroanterior (PA) view. A wire driver is now used to pass a 0.045-inch Kirschner wire across the LT interval, near perpendicular to the axis of this intercarpal space, until the tip of the wire abuts the radial cortex of the lunate (▶Fig. 81.2c). Stable and precise placement of the single wire is assessed via both PA and lateral views of pulsed fluoroscopy as well as wiggling the wire externally, confirming concomitant motion of both the triquetrum and the lunate (▶Fig. 81.2d). The lateral is simply assessed by supinating the forearm passively. When wire placement is deemed acceptable, it is cut just under the skin and the remnant is similarly loaded onto the driver. This wire is similarly passed, near parallel to the first wire and cut under the skin once deemed secure.