Successful surgical and multidisciplinary treatment for complex regional pain syndrome resulting from simple hand laceration: a case report
Article information
Abstract
Complex regional pain syndrome (CRPS) is a chronic pain syndrome characterized by intense hyperalgesia and allodynia, with an unclear etiology and limited definitive treatments. This case involves a 23-year-old female patient who developed CRPS following a simple hand laceration from wine glass shards. After initial primary closure, the patient developed scar contracture at the thumb metacarpophalangeal crease, accompanied by erythema, warmth, heaviness, and hypersensitivity throughout the hand, leading to a CRPS diagnosis. A multidisciplinary approach, including anesthesiology and rehabilitation, confirmed nerve adhesion from scar contracture. Surgical intervention successfully released the adhered scar tissue, fascia, and nerve, followed by rehabilitation therapy. The patient’s functional recovery took nearly 6 months. This case highlights that CRPS can result from minor injuries due to scar-induced nerve entrapment and emphasizes the importance of early diagnosis and interdisciplinary treatment for gradual recovery.
Introduction
Complex regional pain syndrome (CRPS) is a chronic pain syndrome characterized by extreme hyperalgesia and allodynia. CRPS is known to occur due to trauma or surgery. The pathophysiology of this disorder is still under investigation, but nothing has been clearly elucidated. To date, it is believed to be attributed to dysfunction in the central and peripheral nervous systems. The definition and diagnosis of CRPS have evolved over time, and it has been known by terms such as “reflex sympathetic dystrophy,” “causalgia,” and “Sudeck atrophy.” It includes symptoms such as redness and heat, hyperesthesia and/or allodynia, temperature asymmetry, skin color change and/or asymmetry, edema, and abnormal nail growth. Currently, treatments such as physical and occupational therapy, pharmacotherapy, sympathetic block, and surgical management are being attempted, but a definitive treatment method remains under-researched [1,2].
In this paper, we present a case of CRPS induced by nerve scar contracture, a rare causative factor, and introduce the multidisciplinary diagnosis and treatment through collaboration with anesthesiology and rehabilitation medicine.
Case report
This study received an exemption from the Institutional Review Board of The Catholic University of Korea, St. Vincent’s Hospital (Exemption No. VIRB-2022-2841-0001). Written informed consent to publish photographs and case details was obtained from the patients.
A 23-year-old female patient with no significant medical history sustained an injury to the left hand thenar area from a broken wine glass. The patient was transferred to our hospital via another facility due to a suspected nerve injury and underwent general anesthesia for surgical exploration. During the primary physical examination, the patient complained of approximately 30% sensory loss on the radial side of the left thumb. During surgical exploration, no foreign body was observed, and there was no evidence of muscle or tendon injury. The left radial digital nerve was exposed, but there was no significant fascicle damage noted. Only mild involvement of the epineurium was observed, and an epineural suture was performed using a single #9-0 Ethilon suture (Ethicon Inc., Somerville, NJ, USA). After performing extensive irrigation, skin closure was done, followed by application of a splint. On postoperative day (POD) 1, the splint was removed without any issues, and the patient was discharged. On POD 12, total removal of stitches was performed during an outpatient visit.
However, 5 weeks after surgery, scar contracture was observed in the metacarpophalangeal (MCP) crease area, resulting in fixation in a flexed position of the MCP joint. The patient exhibited a positive Tinel’s sign at the scar site. Therefore, triamcinolone injection was administered as a treatment for the scar contracture. Eight weeks after surgery, the patient complained of pain in the ring finger and gabapentin was added, but it was not effective. On postoperative 10 weeks, the patient experienced a heavy sensation in the fingertips and erythema with swelling throughout the entire left palm, along with a complaint of clamminess in the palm (Fig. 1). Therefore, a collaborative approach with anesthesiology and pain medicine was undertaken to diagnose and rule out CRPS. Medications prescribed included pregabalin, acetaminophen/tramadol, nortriptyline, and codeine/ibuprofen.
Following the onset of complex regional pain syndrome, symptoms such as erythema, swelling, pain, and sweating are present throughout the entire left hand. Scar contracture accompanies these symptoms.
However, the patient did not show improvement. Therefore, on postoperative 11 weeks, local anesthesia was administered, and scar revision was performed to assess nerve damage and address scar contracture. During the scar revision procedure, it was observed that the site where neurorrhaphy had been performed in the previous surgery showed adhesions to scar tissue and the thenar fascia. No evidence of neuroma around the nerve was observed. The scar tissue and fascia adhesion site were dissected to release the left thumb’s digital nerve. It was transposed in a medial direction and secured to the surrounding soft tissue using #6-0 Vicryl sutures (Ethicon Inc.). Additionally, scar revision was performed along the crease line using a Z-plasty technique (Fig. 2). Following surgery, rehabilitation therapy, in collaboration with physical medicine and rehabilitation, included transcutaneous electrical nerve stimulation sessions and rehabilitation treatments twice a week. These treatments encompassed passive range of motion exercises, finger stretching, tendon gliding exercises, and opposition exercises.
(A) Photograph from the first operation. The radial digital nerve (yellow arrow) is visible, but no significant nerve damage is observed except for mild detachment of the epineurium. (B) Photograph during scar revision (second operation). Nerve scar capture and fascia adhesion are observed, with the nerve being dissected (white arrow). (C) Postoperative clinical photograph.
On POD 17, there was an improvement in pain; however, active thumb extension remained impossible despite passive movement being possible. Swelling reoccurred in the left hand, with the development of a blister on the third finger and complaints of sensory abnormalities in the ulnar area. Therefore, the patient continued with comprehensive rehabilitation therapy for type 2 CRPS. Four weeks after the second operation, there was an improvement in pain and swelling, but there was persistent extension lag in the thumb’s range of motion. By 7 weeks after the operation, most of the pain, sensation, and sympathetic nervous system-related symptoms had improved; however, the extension lag in the thumb persisted, prompting an electromyography evaluation. The electromyography revealed findings of incomplete left median and ulnar neuropathy. It was determined that pain induced by nerve capture from existing scar tissue led to a protective mechanism causing flexion contracture. Additionally, abnormalities in sensory and motor sympathetic nervous system functions were noted at the dorsal root level involving the ulnar and median nerves. It should be noted that during history taking, it was identified that the patient had prolonged smartphone use while resting. Furthermore, it became evident that after the first surgery, there was prolonged fixation of the thumb in a flexed position.
After 5 months and 2 weeks following the second operation, there was no pain even at rest, and sensory function had fully recovered. Deformities around the fingernail had also improved (Fig. 3). Motor function, including thumb extension and abduction, had recovered, with only slight tremor present but no impact on daily activities (Supplementary Video 1).
(A) Postoperative day (POD) 69 after the first operation. Complex regional pain syndrome was diagnosed, with the beginning of characteristic abnormal nail growth. (B) POD 17 after the second operation. Abnormal nail growth, brittle nails, discoloration, and curvature changes are observed, while normal nail growth is emerging from the base. (C) POD 52 after the second operation. A substantial amount of normal nail growth is evident.
Discussion
CRPS is a challenging condition with unclear pathophysiology and diverse causes, leading to a lack of definitive treatment methods. According to the literature, causes include fractures (42%), blunt traumatic injuries (21%), surgery (12%), carpal tunnel syndrome (7%), and 7% with no clear precipitating event reported. The prevalence is also exceedingly rare at 0.07% [3,4]. CRPS causes severe pain that can result in significant physical and psychological damage to patients, with reports even suggesting it can lead to depression in severe cases. At present, various treatments are being utilized, including physical and occupational therapy, medication, sympathetic nerve blocks, and surgical interventions. However, despite years of research, a definitive treatment method has yet to be established, leaving many patients living in agony [1,2].
When limited to the hand, the exact incidence of CRPS following hand surgery according to the specific injury mechanisms is not yet known. However, in previous literature, Savaş et al. [2] studied the frequency of injury mechanisms in patients who developed CRPS after undergoing surgical treatment for hand injuries. They conducted a study involving a total of 260 patients with hand injuries, of which 174 patients (66.9%) had simple cut lacerations. Forty-three patients (16.5%) had crush injuries, and five patients (1.9%) had blunt trauma. Among them, CRPS developed in 68 patients. Notably, among the patients who developed CRPS, 55.8% had sustained crush injuries, while only 11.5% had cut lacerations. This indicates that although hand CRPS from simple lacerations is occasionally seen in clinical practice, the incidence is significantly lower compared to other injury mechanisms [2].
In this paper, we introduce a case of CRPS that occurred unexpectedly in a simple injury scenario where nerve damage was minimal, contrary to typical expectations for CRPS onset. The patient initially had only mild damage confined to the epineurium, and CRPS was not expected at all in this case. However, symptoms and signs indicative of CRPS, such as pain sensitivity, swelling, erythema, heat sensation, sweating, and nail changes, emerged. Promptly, a multidisciplinary approach involving anesthesiology and pain medicine, as well as rehabilitation medicine, was initiated to attempt treatment.
During the second operation (scar revision), adhesion of scar tissue to the nerve and thenar fascia was observed in this patient. This condition occurred simultaneously with peripheral nerve injury, involving both intraneural and extraneural scar formation. Additionally, issues with nerve gliding planes contributed to the onset of pain and other complex clinical manifestations. Normally, peripheral nerves should glide around joints according to the movement of the joints. They typically allow for elongation of a few millimeters during normal movement. These movements of the nerve occur primarily between the outermost layer of the nerve, the paraneurium (epineurium), and the surrounding connective tissue, or within the nerve itself, between the deep epineurium and perineurium, as well as between each fascicle. This gliding affects the blood flow to the nerve, and under normal gliding systems, it prevents excessive stress due to tension, thereby maintaining sufficient blood flow to the axons and Schwann cells [5]. Therefore, scar formation around nerves can lead to chronic ischemia of the nerve, causing pain during movement and even at rest due to chronic scar tissue exerting pressure on the nerve. Additionally, during the first surgery, dissection around the nerve approximately 1 cm above and below the suspected injury site was performed to clearly identify the damaged area. However, this may have actually promoted scar formation, suggesting that excessive exploration around the nerve should be avoided in the early stages.
Many surgeons have been reluctant to perform surgery on patients experiencing pain, based on longstanding advice to avoid exacerbating symptoms. However, as medical understanding has advanced, it is now evident that surgical intervention may be essential in cases where a nerve injury or compression is causing the pain. Prompt diagnosis and timely treatment initiation are crucial in preventing disease progression and enhancing the quality of life for patients [6]. Furthermore, it should be noted that symptoms may not improve immediately even after successful surgery, often requiring comprehensive rehabilitation therapy for approximately 6 months. Therefore, a multidisciplinary approach is also crucial.
Supplementary materials
Supplementary Video 1 can be found via https://doi.org/10.12790/ahm.24.0032.
Notes
Conflicts of interest
The authors have nothing to disclose.
Funding
None.