Snapping thumb: a rare case of stenosing tenosynovitis of the extensor pollicis longus tendon
- Andrea Lund ,
- Pelle Hanberg ,
- Anders Ditlev Foldager-Jensen and
- Maiken Stilling
- Department of Orthopaedic Surgery, Aarhus University Hospital, Aarhus, Denmark
- Correspondence to Dr Andrea Lund; andrea2290@hotmail.com
Abstract
Tenosynovitis of the extensor pollicis longus (EPL) is rarely reported in patients without rheumatoid arthritis but may lead to thumb snapping as a consequence of EPL stenosing tenosynovitis.
This case presents painful thumb snapping that developed after a wrist trauma and repetitive loading. Ultrasound and MRI were used as diagnostic tools, before surgical release of the EPL in the third extensor compartment was performed. Neither EPL tenosynovitis nor thumb snapping were found at follow-up.
Background
Stenosing tenosynovitis of the extensor tendons has mainly been described for the first extensor compartment also known as De Quervain tenosynovitis. However, stenosing tenosynovitis can also occur in other extensor compartments. Tenosynovitis of the extensor pollicis longus (EPL), which run in the third extensor compartment, is rare, especially for patients not suffering from rheumatoid arthritis. Thumb snapping due to tenosynovitis in the area of Listers’ Tubercle is even more rare.1 2
Nodular swelling and thickening of the EPL tendon and retinacular sheath, respectively, leads to a size discrepancy between the tendon and the cross-sectional area of the third extensor compartment. Repeated tendon movement through a narrowed compartment causes oedema resulting in poor gliding and occasionally locking of the tendon, which may lead to tendon snapping. Early diagnosis and treatment of EPL tenosynovitis is essential in order to prevent tendon rupture.3
Only a few cases of thumb snapping, as a consequence of EPL stenosing tenosynovitis, have previously been reported.4–7 In this case report, one additional case is described with details of both the preoperative and postoperative findings.
Case presentation
A 29-year-old left-hand dominant man employed with package delivery service had manually handled, lifted and delivered many heavy packages every day for years. His medical history reflected no previous illness or injury to the left upper extremity. One day he lifted a 17 kg package with a supination motion using only the left hand and felt a pop and pain central in the wrist.
He presented for medical examination 1.5 week after the trauma because of ongoing pain and a tingling sensation in the three radial fingers of the left hand. He had decreased wrist motion due to pain, especially on wrist extension with radial deviation. Measurement of range of motion in the first carpometacarpal joint was not possible due to pain. Treatment with oral non steroid anti-inflammatory drugs (NSAID) was initiated and 2 weeks later the pain, tingling sensation and motion restriction had resolved. Over the next 2.5 months pain and swelling returned on the dorsal central aspect of the wrist. The thumb snapping returned and the thumb was particularly stiff and painful in the morning. Clinical examination revealed swelling and tenderness over the third extensor compartment with a visible double-snap of the thumb on flexion–extension, see video 1. There was slight loss of wrist flexion–extension and a negative Watsons test.
Investigations
The wrist X-ray was normal. Ultrasound examination showed tenosynovitis in the third extensor compartment with the EPL tendon in continuity. MRI of the wrist presented no sign of bone oedema or joint effusion and bone alignment was normal. A small vascular malformation was present in the anatomical snuffbox but with no direct relation to the site of EPL tenosynovitis. The triangular fibrocartilage complex was normal but the scapholunate ligament presented with oedema and suspicion of a partial ligament rupture. The EPL tendon showed intrasubstance increased signal intensity and a longitudinal split lesion with fluid in the third extensor compartment (figure 1).
Axial T1 Spin Echo (SE) MRI sequence of the left wrist in neutral position before surgery, which demonstrates fluid in the third extensor department indicating tenosynovitis (arrows), at the distal level of the extensorcompartment (A+B) and where the EPL crosses the extensor carpi radialis longus (ECRL) and extensor carpi radialis brevis (ECRB) (C+D). EPL, extensor pollicis longus.
Treatment
Conservative treatment had already been attempted, symptoms were grave, and the tendon showed signs of degeneration on MRI (longitudinal split lesion) and therefore surgery was the first choice. First, wrist arthroscopy using the 3–4, 6R, midcarpal ulnar (MCU) and midcarpal radial (MCR) portals confirmed a Geissler II scapholunate ligament tear, which was treated by arthroscopic thermal shrinkage. Next, we carefully looked for the vascular malformation during open surgery in the anatomical snuffbox without finding it. The deep palmar branch and the dorsal carpal branch from the radial artery were found intact. Finally, a release of the third extensor compartment was performed with a longitudinal incision ulnar to Lister’s Tubercle (figure 2). The EPL tendon was in continuity but presented with a smooth surface covered with thick tenosynovitis, substance thickening (tendinosis) just distal to the extensor retinaculum, and there was excess fluid in the third extensor compartment indicating this as the stenosis site and origin of the tenosynovitis. The extensor retinaculum was elevated subperiosteally and Lister’s Tubercle was removed. The retinaculum was closed leaving the EPL dorsally to the extensor retinaculum in a frictionless subcutaneous bed, see video 2. After surgery, a dorsal plaster was applied for 4 weeks to protect the scapholunate ligament after arthroscopic shrinkage.
Release of the third extensor compartment. (A) The left third extensor compartment is sliced open and tenosynovitis of the EPL tendon is removed. In the picture, a thick mass of tenosynovitis on the tendon is still left at its extracompartmental course (arrow). (B) The EPL tendon is pulled and inspected, the tenosynovitis was only found locally at the extensor compartment. (C) The EPL is held radially and the extensor retinaculum is elevated sharply from Lister’s tubercle, the bone tubercle is flattened, and the extensor retinaculum is closed (arrows) with resorbable sutures. (D) The EPL tendon is left subcutaneously and dorsal to the extensor retinaculum (arrow). EPL, extensor pollicis longus.
Outcome and follow-up
Four weeks postoperatively, the dorsal plaster was removed, and no wrist pain was found. The thumb presented without snapping during flexion–extension and the EPL tendon moved frictionless above the extensor retinaculum on the wrist. Wrist range of movement including flexion–extension, radial–ulnar deviation, supination–pronation was almost normal but with tension in extreme positions. Flexion and extension of the ulnar fingers were normal. Hand therapy exercises were initiated to improve wrist function and regain strength. The patient was advised to refrain from lifting and loading of the hand, wrist and arm for 4 weeks.
The patient attempted to return to the same job with package delivery, but the loads during heavy lifting aggravated his wrist pain and provoked tenosynovitis of both his flexor and extensor tendons of the wrist. Thirteen months after surgery, the patient had recently switched to a delivery service function with a lighter load, the pain and tenosynovitis were gone, and wrist motion was now comparable with that of the contralateral wrist. However, the hand grip strength of the affected wrist was lower as compared with the contralateral wrist probably due to long-term use of wrist orthosis during work and compensation by lifting with the contralateral arm. Thumb range of motion was normal, pain free and without snapping on both sides. Motion ranges are presented in tables 1 and 2.
Bilateral thumb function 13 months after surgery
| Adduction/abduction | 0/70 |
| Extension/flexion | 0/70 |
| Opposition | 0 cm to base of fifth metacarpal bone, Kapandjis score 9 |
Bilateral wrist function 13 months after surgery
| Right hand/left hand | |
| Flexion | 75/70 |
| Extension | 80/80 |
| Radial deviation | 25/25 |
| Ulnar deviation | 35/35 |
| Supination | 85/85 |
| Pronation | 85/85 |
| Hand grip strength | 55 kg/27 kg |
No crepitation at Lister’s Tubercle or along the EPL tendon. Ultrasound and MRI revealed no sign of tenosynovitis in the third compartment (figure 3). Additionally, the small vascular malformation in the anatomical snuffbox was no longer to be found on MRI.
Axial T1 SE MRI of the left wrist in pronation 8 months after surgery. (A) At the axial level of Lister’s tubercle MRI demonstrate a flat tubercle (*) and no sign of tenosynovitis around the extensor pollicis longus (EPL) tendon, which is located subcutaneously above the third extensor compartment. (B) Distal to the radius and the extensor compartments, the EPL cross the ECRL and ECRB tendons subcutaneously, and there is no sign of tenosynovitis around the EPL. ECRB, extensorcarpi radialis brevis; ECRL, extensorcarpi radialis longus .
Discussion
Only five cases have previously been described with thumb snapping as a result of EPL tenosynovitis4–7: three cases as a consequence of falls on a hyperextended wrist4 5 and two cases with a possible association to a strained wrist due to repetitive movements.6 7 This is the first case-linking thumb snapping to a supination trauma preceded by a history of repetitive heavy liftings, a combination that may have contributed to the patient’s condition.
It is well known that bleeding in the third extensor compartment following a distal radius fracture can cause EPL tendon rupture due to a local pressure increase and ischaemia leading to tendon necrosis and rupture.8 Furthermore, it has been demonstrated that EPL can impinge between the base of the third metacarpal and Lister’s Tubercle following hyperextended wrist traumas, leading to either thumb snapping or tendon rupture.4 Tenosynovitis can also be provoked by excessive text messaging in both the first and the third extensor compartment. Chronic tenosynovitis has been associated with attritional tendon rupture, wherefore early diagnosis and timely treatment of tenosynovitis is important.3
In all five described cases with painful thumb snapping on flexion–extension motion, stenosing EPL tenosynovitis was found.4–7 However, the onset symptoms varied between cases. While two cases revealed thumb snapping as the initial symptom,7 three cases experienced uncharacteristic wrist pain 2–3 weeks prior to the onset of thumb snapping.4–6 Pain, swelling, tenderness and crepitus at Lister’s Tubercle has been listed as characteristic and important diagnostic signs of EPL tenosynovitis.2 However, only one described case presented with these symptoms prior to the development of thump snapping.6 Specific clinical testing of EPL function and dysfunction can be done with the ‘thumb off the table-test’, when the palm is flat on the table, and may be useful.
Image techniques such as ultrasound and MRI can help confirm the diagnosis. Ultrasound should be used as the initial image modality of choice for detection of tenosynovitis,9 as it is considered to be more sensitive compared with MRI and allows for dynamic evaluation of the EPL tendon and documentation of eventual snapping during flexion–extension of the thumb.10 Ultrasonic visualised tenosynovitis is characterised by hypoechoic fluid in the tendon sheath, hyperaemia on colour or power Doppler, and synovial hypertrophy with or without hypervascularisation.11 Ultrasound may also be used to guide intra sheath steroid injections. On MRI, tenosynovitis is characterised by the presence of EPL tendon thickness, increased intrasubstance signal, synovitis, scarring of the tendon sheath and fluid in the third extensor compartment. All of these signs were present on the MRI of the presented case.7 Furthermore, radial artery aneurysm secondary to dynamic entrapment of the EPL tendon may present on MRI12 or ultrasound, which was also seen in our case.
Only in two out of the five cases available in the literature conservative treatment was attempted before heading to surgery.5 6 No effect was found by neither immobilisation5 nor oral use of NSAIDs combined with rest.6 However, in the present case, a short-term effect of immobilisation and oral NSAID treatment was found, and if the patient had not gone back to heavy labour perhaps it would have been sufficient. Local steroid injection into the EPL tendon sheath was attempted in one case in the literature and relieved pain for a couple of months before return of symptoms.6 Intratendinous steroid injections pose a risk of spontaneous tendon rupture due to the known attritional effects of steroids on collagen.13 14 Steroid injection prior to surgery was not attempted in the present case.
The EPL tendon has an oblique course in the third extensor compartment where it passes around Lister’s tubercle. At this point, the tendon sheath is very tight. This may predispose to tendon attrition and risk of tendon rupture with synovitis. An EPL tendon rupture is a serious complication for a young patient with heavy labour and require tendon reconstruction by free tendon grafting (often palmaris longus) or transfer of the extensor indicis proprius tendon to the EPL. This requires long rehabilitation, sick leave and leaves hand function less optimal. In contrast, operative treatment with timely EPL tendon release is a minimal soft-tissue trauma with prompt effect, small risk of complications and quick rehabilitation. Most often, the EPL is left outside of the extensor retinaculum in a subcutaneous bed, and the procedure has no risk of secondary tendon bowstringing. Importantly, when approaching a case of EPL tenosynovitis with surgery, the surgeon should always be prepared to perform free tendon grafting or tendon transposition in case of tendon necrosis/attrition.
The literature describing EPL stenosing tenosynovitis is casuistic but with a clear description of symptom relief after surgical release of the EPL tendon in the third extensor compartment. Therefore, operative treatment is recommended in the early course in order to prevent risk of attritional tendon rupture.
Learning points
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In a painful thumb with snapping on flexion–extension motion, extensor pollicis longus stenosing tenosynovitis should be considered.
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Ultrasound and MRI may be helpful in the diagnostics.
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Treatment recommendation is surgical release before tendon rupture occurs.
Ethics statements
Footnotes
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Contributors Idea for the article: MS. Literature search: AL, PH, ADF-J, MS. First draft of the manuscript: AL. Critical revision of the manuscript: PH, MS, ADF-J. Guarantor: AL, PH, ADF-J and MS. Final acceptance of the manuscript and submission: AL, PH, ADF-J and MS.
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Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
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Competing interests None declared.
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Provenance and peer review Not commissioned; externally peer reviewed.
- © BMJ Publishing Group Limited 2021. No commercial re-use. See rights and permissions. Published by BMJ.
References
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