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Hand Surgery, Vol. 19, No. 2 (2014) 237–239 © World Scientific Publishing Company DOI: 10.1142/S0218810414720174
A CASE REPORT OF TRIGGER WRIST ASSOCIATED WITH CARPAL TUNNEL SYNDROME CAUSED BY AN INTRAMUSCULAR LIPOMA Paul Berlund and Michael Kalamaras Department of Orthopaedics, Gold Coast University Hospital Gold Coast, Australia Received 18 September 2013; Revised 27 January 2014; Accepted 28 January 2014 ABSTRACT Triggering at the wrist with finger movement is an uncommon presentation. We present the case of a 46 year old male with painful wrist triggering with associated carpal tunnel syndrome caused by an intramuscular lipoma of the lumbrical muscle. As far as we are aware this is only the second documented case of wrist triggering caused by an intramuscular limpoma. Surgical removal of the tumour led to a resolution of the patients symptoms. We review the literature and discuss other published cases of this rare presentation. Keywords: Carpal Tunnel; Wrist Triggering; Lipoma.
INTRODUCTION
sensation at the right wrist that progressed over months to painful triggering on finger flexion. Paraesthesia, distributed over the volar radial three and a half digits of the hand developed after the onset of the wrist triggering. The paraesthesia progressively worsened with time; it was particularly bad when performing manual work and during sleep. On examination, triggering was evident with a palpable and audible clunk over the carpal tunnel when making a fist and was noted specifically on flexion of the distal inter-phalangeal joint of the ring and middle fingers. A smooth, firm, mobile mass, previously unknown to the patient, could be palpated within the hand and wrist depending on position of finger flexion. The mass was non tender and could be felt to travel with flexor tendon movement in the wrist and hand. Tinel’s sign was
Triggering at the carpal tunnel on finger movement, or \trigger wrist", is a rare presentation often associated with synovial and neoplastic pathologies. We describe such a case in association with carpal tunnel syndrome caused by an intramuscular lipoma of the lumbrical muscle of the middle finger. We review the literature for similar clinical findings and discuss this unusual case.
CASE REPORT A 46-year-old male, right-handed, manual labourer, presented with a history carpal tunnel syndrome with associated carpal tunnel triggering. Symptoms began as a painless clicking
Correspondence to: Dr. Paul Berlund, Department of Orthopaedics, Gold Coast University Hospital, 1 Hospital Boulevard, Southport, Queensland 4215, Australia. Tel: (þ61) 7-5687-0000, E-mail: Paul _ [email protected] 237
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Fig. 1 Magnetic resonance imaging demonstrating the fatty mass (arrow) that appears to be lying between the third and fourth flexor digitorum profundus and flexor digitorum superficialis tendons.
positive over the carpal tunnel of the right wrist with a negative Phalens’ sign. The patient had a history of several subcutaneous lipomas in other areas. Nerve conduction studies were performed with fingers in extension in a relaxed state and demonstrated severe sensory conduction delay of the median nerve at the wrist (Table 1). Magnetic resonance imaging demonstrated a solid, soft tissue mass of intermediate signal intensity on T1 sequence with fat suppression and without contrast enhancement (Fig. 1). Under general anaesthesia, an open carpal tunnel decompression and surgical exploration was performed. Thickened flexor synovium of the flexor digitorum profundus was noted and sent for histopathology (Fig. 2). The mass was not immediately recognisable visually but was palpable within the lumbrical muscle mass of the middle finger. The muscle was dissected carefully revealing a well circumscribed tumour (1:5 1 1 cm). Macroscopically, the tumour was cream coloured, firm, rubbery and easily separated from the muscle fibers. The mass was seen to pass through the Table 1 Sensory Nerve Conduction Right wrist Left wrist Motor nerve conduction Right (wrist-elbow)
Nerve Conduction Studies. Distal Latency (ms) Median Nerve
Distal Latency (ms) Ulna Nerve
5.4 4.6 Distal latency (ms) 5.6
3.8 4.4
Sensory nerve conduction studies comparing the distal latency of the median and ulna nerve (control) on the ipsilatal side over an identical distance. A difference of greater than 0.2 ms suggests carpal tunnel delay. In motor conduction studies to assess the carpal tunnel, distal latency of more than 4.0 ms suggest carpal tunnel delay.
Fig. 2 The tumour within the belly of the dissected lumbrical muscle of the middle finger.
carpal tunnel, proximal to distal, with finger flexion and entered the space of Parona with a snap. Histological examination found the tumour to be composed of adipocytes with bands of fibrosis and myxoiod areas reported as a fibrolipoma (a variant of a lipoma). The synovium showed no evidence of inflammation or malignancy. The patient was reviewed two weeks post-operatively and his wound had healed. His symptoms had resolved and there was no longer any triggering or discomfort. There has been no recurrence of symptoms since.
DISCUSSION Few cases have been published that describe the phenomenon of carpal tunnel triggering with finger movement. Suematsu (1985) proposed that this triggering occurs as a mass passes through the narrow distal segment of the carpal tunnel.1 They devised a classification system for wrist triggering based upon flexor tendon sheath pathologies. In their review, 16 of the 18 cases were associated with carpal tunnel syndrome. They described type A — tumours, type B — anomalous muscle belly, and type C — tumour plus anomalous muscle belly.1 The above case described would be designated as type A. As far as we know, the only other case of an intramuscular lipoma causing wrist triggering was associated with an anomalous accessory muscle belly to the flexor digitorum profundus of the middle finger2 and as such, it would be classified as a type C. Two further cases of the above presentation caused by a lipoma have been reported, however these tumours were not intramuscular
May 21, 2014
10:15:50am
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Trigger Wrist with Carpal Tunnel Syndrome Caused by Intramuscular Lipoma
and were associated with the flexor tenosynovium.3,4 Resolution of symptoms post excision of the lesion occurred in all of the above cases. A literature review of wrist triggering is complicated by the lack of an eponymous name and variability in the site or pathological nature of the cause. Many authors disagree with the term trigger wrist to describe the above cases, and as such there is much variability in the nomenclature used with titles such as pseudo-triggering, wrist snapping, wrist clicking or simply reported as carpal tunnel syndrome.5 A review of \trigger wrist" by Giannikas (2007) noted that wrist snapping or triggering can also been caused by extensor tendon and intra-carpal pathologies in addition to the causes offered by Sumetasu (1985), albeit more rarely.5 An alternative classification system, first proposed by Ogino (1994), describes wrist triggering as caused by (1) finger movement, (2) wrist movement or (3) forearm pronation or supination.6 Combining the two systems would lead to the most accurate description of this rare clinical entity. In this patient, we would classify the case as \trigger wrist, caused by finger movement (Ogino type 1), due to a lipoma (Suematsu type A)". Although this is a rare presentation, there are several case reports of similar clinical findings with slightly differing causes in the literature. In this case, the lipoma was embedded within the lumbrical muscle and would not have been easily located without careful and thorough surgical exploration performed
239
because of the presence of triggering. If the lesion had been smaller, it may have not caused triggering and would almost certainly have been missed during routine or revision carpal tunnel release surgery. This case highlights the desirability of a MRI scan of the wrist, hand and forearm as a pre-operative investigation prior to revision surgery in cases of failed carpal tunnel surgery with persistent median nerve compression across the wrist.
References 1. Suematsu N, Hirayama T, Takemitsu Y, Trigger wrist and flexor tenosynovitits, J Hand Surg 10B:121–123, 1985. 2. Cossey AJ, Stranks GJ, Intramuscular lipoma in an anomalous muscle belly of the middle finger lumbrical as a cause of carpal tunnel syndrome and trigger wrist, Orthopaedics 26(1):85–86, 2003. 3. Imai S, Kodama N, Matsusue Y, Intrasynovial lipoma causing trigger wrist and carpal tunnel syndrome, Scand J Plast Reconstr Surg Hand Surg 42(6):328–330, 2008. 4. Sonoda H, Takasita M, Taira H, Hifashi T, Tsumura H, Carpal tunnel syndrome and trigger wrist caused by a lipoma arising from flexor tensosynovium: A case report, J Hand Surg Am 27(6):1056–1058, 2002. 5. Giannikas D, Karabasi A, Dimakopoulos P, Trigger, J Hand Surg Eur 32(2):214–216, 2007. 6. Ogino T, Kato H, Ohshio I, Trigger wrist induced by finger movement, Pathogenesis and differential diagnosis, Handchir Mikrochir Plast Chir 26(1):3–6, 1994.
Copyright of Hand Surgery is the property of World Scientific Publishing Company and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
10:15:44am
WSPC/135-HS
FA1
1472017
Hand Surgery, Vol. 19, No. 2 (2014) 237–239 © World Scientific Publishing Company DOI: 10.1142/S0218810414720174
A CASE REPORT OF TRIGGER WRIST ASSOCIATED WITH CARPAL TUNNEL SYNDROME CAUSED BY AN INTRAMUSCULAR LIPOMA Paul Berlund and Michael Kalamaras Department of Orthopaedics, Gold Coast University Hospital Gold Coast, Australia Received 18 September 2013; Revised 27 January 2014; Accepted 28 January 2014 ABSTRACT Triggering at the wrist with finger movement is an uncommon presentation. We present the case of a 46 year old male with painful wrist triggering with associated carpal tunnel syndrome caused by an intramuscular lipoma of the lumbrical muscle. As far as we are aware this is only the second documented case of wrist triggering caused by an intramuscular limpoma. Surgical removal of the tumour led to a resolution of the patients symptoms. We review the literature and discuss other published cases of this rare presentation. Keywords: Carpal Tunnel; Wrist Triggering; Lipoma.
INTRODUCTION
sensation at the right wrist that progressed over months to painful triggering on finger flexion. Paraesthesia, distributed over the volar radial three and a half digits of the hand developed after the onset of the wrist triggering. The paraesthesia progressively worsened with time; it was particularly bad when performing manual work and during sleep. On examination, triggering was evident with a palpable and audible clunk over the carpal tunnel when making a fist and was noted specifically on flexion of the distal inter-phalangeal joint of the ring and middle fingers. A smooth, firm, mobile mass, previously unknown to the patient, could be palpated within the hand and wrist depending on position of finger flexion. The mass was non tender and could be felt to travel with flexor tendon movement in the wrist and hand. Tinel’s sign was
Triggering at the carpal tunnel on finger movement, or \trigger wrist", is a rare presentation often associated with synovial and neoplastic pathologies. We describe such a case in association with carpal tunnel syndrome caused by an intramuscular lipoma of the lumbrical muscle of the middle finger. We review the literature for similar clinical findings and discuss this unusual case.
CASE REPORT A 46-year-old male, right-handed, manual labourer, presented with a history carpal tunnel syndrome with associated carpal tunnel triggering. Symptoms began as a painless clicking
Correspondence to: Dr. Paul Berlund, Department of Orthopaedics, Gold Coast University Hospital, 1 Hospital Boulevard, Southport, Queensland 4215, Australia. Tel: (þ61) 7-5687-0000, E-mail: Paul _ [email protected] 237
May 21, 2014
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P. Berlund & M. Kalamaras
Fig. 1 Magnetic resonance imaging demonstrating the fatty mass (arrow) that appears to be lying between the third and fourth flexor digitorum profundus and flexor digitorum superficialis tendons.
positive over the carpal tunnel of the right wrist with a negative Phalens’ sign. The patient had a history of several subcutaneous lipomas in other areas. Nerve conduction studies were performed with fingers in extension in a relaxed state and demonstrated severe sensory conduction delay of the median nerve at the wrist (Table 1). Magnetic resonance imaging demonstrated a solid, soft tissue mass of intermediate signal intensity on T1 sequence with fat suppression and without contrast enhancement (Fig. 1). Under general anaesthesia, an open carpal tunnel decompression and surgical exploration was performed. Thickened flexor synovium of the flexor digitorum profundus was noted and sent for histopathology (Fig. 2). The mass was not immediately recognisable visually but was palpable within the lumbrical muscle mass of the middle finger. The muscle was dissected carefully revealing a well circumscribed tumour (1:5 1 1 cm). Macroscopically, the tumour was cream coloured, firm, rubbery and easily separated from the muscle fibers. The mass was seen to pass through the Table 1 Sensory Nerve Conduction Right wrist Left wrist Motor nerve conduction Right (wrist-elbow)
Nerve Conduction Studies. Distal Latency (ms) Median Nerve
Distal Latency (ms) Ulna Nerve
5.4 4.6 Distal latency (ms) 5.6
3.8 4.4
Sensory nerve conduction studies comparing the distal latency of the median and ulna nerve (control) on the ipsilatal side over an identical distance. A difference of greater than 0.2 ms suggests carpal tunnel delay. In motor conduction studies to assess the carpal tunnel, distal latency of more than 4.0 ms suggest carpal tunnel delay.
Fig. 2 The tumour within the belly of the dissected lumbrical muscle of the middle finger.
carpal tunnel, proximal to distal, with finger flexion and entered the space of Parona with a snap. Histological examination found the tumour to be composed of adipocytes with bands of fibrosis and myxoiod areas reported as a fibrolipoma (a variant of a lipoma). The synovium showed no evidence of inflammation or malignancy. The patient was reviewed two weeks post-operatively and his wound had healed. His symptoms had resolved and there was no longer any triggering or discomfort. There has been no recurrence of symptoms since.
DISCUSSION Few cases have been published that describe the phenomenon of carpal tunnel triggering with finger movement. Suematsu (1985) proposed that this triggering occurs as a mass passes through the narrow distal segment of the carpal tunnel.1 They devised a classification system for wrist triggering based upon flexor tendon sheath pathologies. In their review, 16 of the 18 cases were associated with carpal tunnel syndrome. They described type A — tumours, type B — anomalous muscle belly, and type C — tumour plus anomalous muscle belly.1 The above case described would be designated as type A. As far as we know, the only other case of an intramuscular lipoma causing wrist triggering was associated with an anomalous accessory muscle belly to the flexor digitorum profundus of the middle finger2 and as such, it would be classified as a type C. Two further cases of the above presentation caused by a lipoma have been reported, however these tumours were not intramuscular
May 21, 2014
10:15:50am
WSPC/135-HS
FA1
1472017
Trigger Wrist with Carpal Tunnel Syndrome Caused by Intramuscular Lipoma
and were associated with the flexor tenosynovium.3,4 Resolution of symptoms post excision of the lesion occurred in all of the above cases. A literature review of wrist triggering is complicated by the lack of an eponymous name and variability in the site or pathological nature of the cause. Many authors disagree with the term trigger wrist to describe the above cases, and as such there is much variability in the nomenclature used with titles such as pseudo-triggering, wrist snapping, wrist clicking or simply reported as carpal tunnel syndrome.5 A review of \trigger wrist" by Giannikas (2007) noted that wrist snapping or triggering can also been caused by extensor tendon and intra-carpal pathologies in addition to the causes offered by Sumetasu (1985), albeit more rarely.5 An alternative classification system, first proposed by Ogino (1994), describes wrist triggering as caused by (1) finger movement, (2) wrist movement or (3) forearm pronation or supination.6 Combining the two systems would lead to the most accurate description of this rare clinical entity. In this patient, we would classify the case as \trigger wrist, caused by finger movement (Ogino type 1), due to a lipoma (Suematsu type A)". Although this is a rare presentation, there are several case reports of similar clinical findings with slightly differing causes in the literature. In this case, the lipoma was embedded within the lumbrical muscle and would not have been easily located without careful and thorough surgical exploration performed
239
because of the presence of triggering. If the lesion had been smaller, it may have not caused triggering and would almost certainly have been missed during routine or revision carpal tunnel release surgery. This case highlights the desirability of a MRI scan of the wrist, hand and forearm as a pre-operative investigation prior to revision surgery in cases of failed carpal tunnel surgery with persistent median nerve compression across the wrist.
References 1. Suematsu N, Hirayama T, Takemitsu Y, Trigger wrist and flexor tenosynovitits, J Hand Surg 10B:121–123, 1985. 2. Cossey AJ, Stranks GJ, Intramuscular lipoma in an anomalous muscle belly of the middle finger lumbrical as a cause of carpal tunnel syndrome and trigger wrist, Orthopaedics 26(1):85–86, 2003. 3. Imai S, Kodama N, Matsusue Y, Intrasynovial lipoma causing trigger wrist and carpal tunnel syndrome, Scand J Plast Reconstr Surg Hand Surg 42(6):328–330, 2008. 4. Sonoda H, Takasita M, Taira H, Hifashi T, Tsumura H, Carpal tunnel syndrome and trigger wrist caused by a lipoma arising from flexor tensosynovium: A case report, J Hand Surg Am 27(6):1056–1058, 2002. 5. Giannikas D, Karabasi A, Dimakopoulos P, Trigger, J Hand Surg Eur 32(2):214–216, 2007. 6. Ogino T, Kato H, Ohshio I, Trigger wrist induced by finger movement, Pathogenesis and differential diagnosis, Handchir Mikrochir Plast Chir 26(1):3–6, 1994.
Copyright of Hand Surgery is the property of World Scientific Publishing Company and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
