**2. Patients and methods**

The clinical and operative details of all patients who underwent peripheral nerve surgery at the neurosurgery department of Amrita Institute of Medical Sciences, Amrita University in Kochi, India over a period of 5 years from January 2010 till January 2015 were obtained from the hospital database and retrospectively reviewed. This department is a major neurosurgical referral center located in south-west of India serving both local and international patients. The senior author (AP) was responsible for the clinical and surgical management of all patients under review. The spectrum of cases ranged from nerve injuries and peripheral nerve sheath tumors to nerve entrapment syndromes. Short descriptions of the key approach and techniques which we used are briefly detailed as follows (with illustrations):

#### **2.1. Nerve repair surgical technique**

All our nerve repairs involved microanastomosis with 10.0 nylon epineural sutures (1–3 per coaptation) and fibrin glue, as described in the literature [45]. Our cable graft sources included the sural nerve, medial antebrachial cutaneous nerve (MACN), and occasionally the greater auricular nerve in infants. Some of our employed techniques for the extraplexal repairs included Somsak's selective distal neurotization of the axillary nerve with branch to long head of triceps [46], posterior approach and transfer of the spinal accessory nerve to the

particularly for injuries involving the brachial plexus [44]. The most crucial aspect of planning surgical intervention in brachial plexus injury is selecting the timing of surgery [8]—preferably explored within 5 months after injury [8, 13]. This might be as early as 2 months for pan-plexus injuries which have demonstrated no improvement or as late as 5–6 months for distal neurotization repairs for upper plexus injuries. Generally, the armamentarium of the peripheral nerve surgeon includes (1) the initial history and examination, (2) preoperative electrophysiology, (3) preoperative rehabilitation, (4) longitudinal preoperative clinical and electrophysiological course (i.e., recovery/no recovery), (5) preoperative radiological assessment, (6) intraoperative anatomic study, (7) intraoperative electrophysiology, (8) operative

However, this ideal kind of practice is obtainable mainly in the developed countries. Dedicated neurosurgical peripheral nerve surgery centers are still quite few in India and most other developing countries where majority of these patients either remain untreated or are palliated with physiotherapy as the only intervention, mainly as a result of lack of the required expertise and the necessary facilities. In this article, we looked at the pattern and trend of these problems in our practice, and present our early experience and outcomes, along with a brief review of previously documented results on similar surgical problems in the literature. Finally, we summarize the general principles and currently accepted practice guidelines

The clinical and operative details of all patients who underwent peripheral nerve surgery at the neurosurgery department of Amrita Institute of Medical Sciences, Amrita University in Kochi, India over a period of 5 years from January 2010 till January 2015 were obtained from the hospital database and retrospectively reviewed. This department is a major neurosurgical referral center located in south-west of India serving both local and international patients. The senior author (AP) was responsible for the clinical and surgical management of all patients under review. The spectrum of cases ranged from nerve injuries and peripheral nerve sheath tumors to nerve entrapment syndromes. Short descriptions of the key approach and techniques which we used are briefly detailed as

All our nerve repairs involved microanastomosis with 10.0 nylon epineural sutures (1–3 per coaptation) and fibrin glue, as described in the literature [45]. Our cable graft sources included the sural nerve, medial antebrachial cutaneous nerve (MACN), and occasionally the greater auricular nerve in infants. Some of our employed techniques for the extraplexal repairs included Somsak's selective distal neurotization of the axillary nerve with branch to long head of triceps [46], posterior approach and transfer of the spinal accessory nerve to the

procedures, and (9) postoperative rehabilitation.

required for optimal outcomes.

126 Treatment of Brachial Plexus Injuries

**2. Patients and methods**

follows (with illustrations):

**2.1. Nerve repair surgical technique**

**Figure 1.** Intraoperative pictures of a sample extraplexal neurotization repair of pan-plexus injury. (A) Full-length phrenic nerve transfer to medial root of the median nerve for prehensile hand function and coaptation of contralateral C7 (Cont. C7) to the posterior cord for axillary and radial nerve functions. (B) Sural nerve cable graft in the same panplexus repair to neurotize the musculocutaneous nerve (MCN) from the spinal accessory nerve (SAN) for elbow flexion. The coaptation was made in the infraclavicular space into the MCN distal to the branch to the coracobrachialis. (C) Supraclavicular coaptation of ipsilateral C4 motor root and SAN as donor sources into sural nerve cable graft neurotizing the MCN.

suprascapular nerve for shoulder abduction, Oberlin I selective transfer of ulnar nerve fascicle to the musculocutaneous nerve and Oberlin II transfer of branch to brachialis with median nerve motor fascicle for elbow flexion [34]. Our extraplexal transfer techniques also used included contralateral C7 transfer with cable grafts tunneled through the prevertebral space (in 11 patients) to the posterior division of upper trunk for axillary and radial nerve reinnervation and/or the medial cord/branches in OBPI (obstetric brachial plexus injury) for hand function, and thoracoscopically harvested full length phrenic nerve transfer to medial root of median nerve for hand prehensile function (in 4 patients) (**Figure 1A**–**C**). Donor fascicle functional integrity and recipient nerve nonfunctionality was confirmed by the presence or absence of innervated muscle contraction in response to direct monopolar nerve stimulation. Post-operative immobilization of the affected limb was maintained for 3 weeks, and thereafter patients were commenced on a rigorous rehabilitation protocol by the second author (RS) as early as possible.

#### **2.2. PNST (peripheral nerve sheath tumor) excision surgical technique**

Under general anesthesia or regional anesthesia, the affected nerve segment was exposed, the epineurium was incised and tumor dissected in its subcapsular plane for PNSTs to ensure that non-involved fascicles remained functionally intact (**Figure 2c**). The entire limb was prepared and draped in order to assess all individual muscles with direct nerve stimulation as per the resection needs. Either direct NAP (nerve action potential) was recorded across the segment (2 cases) or absence of stimulation-induced target muscle twitching was ascertained before sacrificing the primary fascicle giving rise to the PNST. For malignant peripheral nerve sheath tumors (MPNSTs), an oncological wide resection at least 2–3 cm proximal and distal to the tumor, sacrificing the entire parent nerve, was done followed by functionally matched fascicular repair using sural nerve cable grafts (**Figure 3**). MPNSTs were often diagnosed preoperatively using FDG-PET (fluorodeoxyglucose positron emission tomography) scan to counsel and plan for nerve sacrifice and immediate repair.

**Figure 2.** (A–C) Excision of a benign peripheral nerve sheath tumor. The affected nerve segment was first exposed, followed by incision of the epineurium and the tumor was then dissected out complete in its subcapsular plane.

move against gravity, it was useful to add functional tasks into the exercise programme since motor coordination is as important as strength in recovery. With this process, the patient would gradually develop "different" ways of doing old tasks to compensate for weakness of the primary effector muscle. This was achieved by utilizing the secondary effector muscles

**Figure 4.** (A, B) Guyon's canal release. Notice the extent of the skin incision to both the wrist and palmar line (A) to

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ensure adequate exposure and release of the ulnar nerve and artery at the level of the canal.

If there was little hope of recovering function at this point, then focusing on stabilizing the involved muscles above and below became more practical but if the chances of functional recovery were high, then training the concerned muscle to become activated at the correct time in the kinetic chain became more useful than just purely strengthening it. Once the reinnervation waiting period was over, one of three patterns would usually emerge: (1) the patient recovered function in the limb and used it, (2) the nerve failed to reach and innervate the muscle, or (3) the reinnervation occurred but disuse would have reduced cortical representation and then, the patient may not know "how to" use the muscle. Electrophysiology was quite useful in differentiating such cases, and modifying the rehabilitation plan at this

Our measurement of functional outcomes following surgery was defined as follows based on

• No improvement in power = only flicker of movement of the affected muscle groups (or

• Slight or mild improvement in power of affected muscle groups or the involved limb = MRC

• Significant improvement in power of affected muscle groups or the involved limb = MRC

stage taken into consideration depending on which of these patterns was the case.

the Medical Research Council (MRC) motor power grading system [4, 20].

which changed the appearance of task performance.

**2.4. Outcome analysis**

2–3

4–5

affected limb) = MRC 0–1

**Figure 3.** (A–D) Excision of a malignant peripheral nerve sheat tumor. Notice the extent of involvement of the affected limb. An oncological wide resection proximal and distal to the tumor was done along with excision of the involved parent nerve (C), followed by functionally matched fascicular repair using harvested cable grafts, as shown in (D).

#### **2.3. Nerve entrapment release surgical technique**

Nerve entrapments distal to the shoulder (cubital tunnel, PIN entrapment, Guyon's canal entrapment) were operated under regional (supraclavicular block) or local anesthesia. Previously described techniques were followed [1, 2, 21, 30] (**Figure 4A** and **B**).

Following surgery in each patient, the limb was immobilized with a splint for 2–3 weeks before commencing physiotherapy, to allow for epineural healing without tension at the anastomosis. Once the concerned limb was mobilized, our primary goals were prevention of contracture and prevention of complex regional pain syndrome (CRPS) following muscle reinnervation, by starting with passive ROM (range of motion). Once a flicker of contraction was found in the concerned muscles, we began isolating and strengthening them with gravity initially, progressing to "against gravity," and then with resistance. Once the patient could

**Figure 4.** (A, B) Guyon's canal release. Notice the extent of the skin incision to both the wrist and palmar line (A) to ensure adequate exposure and release of the ulnar nerve and artery at the level of the canal.

move against gravity, it was useful to add functional tasks into the exercise programme since motor coordination is as important as strength in recovery. With this process, the patient would gradually develop "different" ways of doing old tasks to compensate for weakness of the primary effector muscle. This was achieved by utilizing the secondary effector muscles which changed the appearance of task performance.

If there was little hope of recovering function at this point, then focusing on stabilizing the involved muscles above and below became more practical but if the chances of functional recovery were high, then training the concerned muscle to become activated at the correct time in the kinetic chain became more useful than just purely strengthening it. Once the reinnervation waiting period was over, one of three patterns would usually emerge: (1) the patient recovered function in the limb and used it, (2) the nerve failed to reach and innervate the muscle, or (3) the reinnervation occurred but disuse would have reduced cortical representation and then, the patient may not know "how to" use the muscle. Electrophysiology was quite useful in differentiating such cases, and modifying the rehabilitation plan at this stage taken into consideration depending on which of these patterns was the case.

#### **2.4. Outcome analysis**

**2.3. Nerve entrapment release surgical technique**

128 Treatment of Brachial Plexus Injuries

Nerve entrapments distal to the shoulder (cubital tunnel, PIN entrapment, Guyon's canal entrapment) were operated under regional (supraclavicular block) or local anesthesia.

**Figure 3.** (A–D) Excision of a malignant peripheral nerve sheat tumor. Notice the extent of involvement of the affected limb. An oncological wide resection proximal and distal to the tumor was done along with excision of the involved parent nerve (C), followed by functionally matched fascicular repair using harvested cable grafts, as shown in (D).

**Figure 2.** (A–C) Excision of a benign peripheral nerve sheath tumor. The affected nerve segment was first exposed, followed by incision of the epineurium and the tumor was then dissected out complete in its subcapsular plane.

Following surgery in each patient, the limb was immobilized with a splint for 2–3 weeks before commencing physiotherapy, to allow for epineural healing without tension at the anastomosis. Once the concerned limb was mobilized, our primary goals were prevention of contracture and prevention of complex regional pain syndrome (CRPS) following muscle reinnervation, by starting with passive ROM (range of motion). Once a flicker of contraction was found in the concerned muscles, we began isolating and strengthening them with gravity initially, progressing to "against gravity," and then with resistance. Once the patient could

Previously described techniques were followed [1, 2, 21, 30] (**Figure 4A** and **B**).

Our measurement of functional outcomes following surgery was defined as follows based on the Medical Research Council (MRC) motor power grading system [4, 20].


The evaluations were carried out at 6 months, 1 year and 2 years after surgery at follow-up in our outpatient clinics.

As shown in **Table 3**, the majority of the injuries were repaired with various extraplexal neurotization transfers alone (25.8%), followed by repair with various combinations of extraplexal transfers and intraplexal neurotizations (22.6%), while 19.4% had repair with only intraplexal neurotizations. **Figure 5** summaries all surgeries done over the 5 year period. Brachial plexus

Starting A Peripheral Nerve Surgery Unit in an Area of Limited Resources - Our Experience

Peripheral nerve sheath tumors 21 55.3% Peripheral nerve entrapments 8 21.1% Chronic neuralgia 5 13.2% Common peroneal nerve injury 1 2.6% Ulnar nerve injury 3 7.9% Total **38 100.0%**

Intraplexal neurotization 6 19.4% Extraplexal neurotization/distal nerve transfers 8 25.8% Combined intra + extraplexal neurotizations 7 22.6% Exploration with internal/external neurolysis 3 9.7% Microsurgical dorsal root entry zone lesioning (DREZ-otomy) 4 12.9% Only microsurgical exploration + neurophysiological studies 3 9.7% Total 30 100%

**Figure 5.** Summary of various peripheral nerve surgeries done over the five year period under review. Brachial plexus

**Table 2.** Distribution of surgery for other lesions (adults and children).

**Table 3.** Breakdown of all procedures done for brachial plexus injuries.

injury repairs and PNST excisions formed the bulk of the procedures.

**n Percentage**

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**n Percentage**

#### **3. Results**

A total of 68 surgeries were completed in 58 patients for various peripheral nerve disorders over the 5-year period. There was an average of about 13.2 surgeries per year, with an increasing frequency as the programme developed. The age of the patients ranged from 2 month to 68 years, with a sex distribution of 41 males and 17 females (ratio of 2.4:1). Overall mean time of presentation was at 18.3 months either post-injury or following onset of symptoms for nontraumatic peripheral nerve problems, with the earliest presentation being 1 day post-obstetric brachial plexus injury in a newborn at birth and the latest being 15 years in 2 patients (one with a left ulnar nerve nodule and the other with a left brachial plexus PNST respectively). The majority of the cases were for brachial plexus injuries (n = 30, 44.1%) comprising 19 adult surgeries and 11 pediatric surgeries. Among the 19 adult surgeries, there were 10 procedures for pan-brachial plexus injuries, 7 for upper brachial plexus injuries and only 2 for lower brachial plexus injuries (**Table 1**). Of the 11 pediatric surgeries, 9 were for obstetric brachial pan-plexus injuries (OBPI—Erb's-Klumpke type) with one of the patients undergoing surgery twice while the remaining 2 were for road traffic accident traumatic injuries (**Table 1**). There were 21 excisions for peripheral nerve sheath tumors of which four were malignant, with one of these three patients requiring surgery twice (**Table 2**). There were 8 peripheral nerve entrapments comprising 3 posterior interosseous nerve entrapments, 3 cubital tunnel syndromes, 1 thoracic outlet syndrome and 1 Guyon's canal entrapment syndrome. The remaining 9 surgeries included repair for 2 patients with penetrating ulnar nerve injury, 2 patients with iatrogenic nerve injuries from PNST surgeries done elsewhere (brachial plexus and common peroneal respectively), and procedures for chronic neuralgia (which included 3 DREZ-otomies, image-guided radiofrequency lesioning, open neurotomy of lateral cutaneous nerve of the right forearm and selective fascicular neurectomy of the left distal ulnar nerve). Among the benign lesions, 12 (57.1%) were benign schwannomas, while the remaining 42.9% consisted of various other lesions. Of note, 3 patients undergoing PNST using the fascicular-sparing subcapsular dissection technique noted post-op sensory deficits or paresthesias which were generally transient and none was noted to have any motor deficits.


**Table 1.** Distribution of surgery for adult and pediatric brachial plexus injuries.

As shown in **Table 3**, the majority of the injuries were repaired with various extraplexal neurotization transfers alone (25.8%), followed by repair with various combinations of extraplexal transfers and intraplexal neurotizations (22.6%), while 19.4% had repair with only intraplexal neurotizations. **Figure 5** summaries all surgeries done over the 5 year period. Brachial plexus


**Table 2.** Distribution of surgery for other lesions (adults and children).

The evaluations were carried out at 6 months, 1 year and 2 years after surgery at follow-up in

A total of 68 surgeries were completed in 58 patients for various peripheral nerve disorders over the 5-year period. There was an average of about 13.2 surgeries per year, with an increasing frequency as the programme developed. The age of the patients ranged from 2 month to 68 years, with a sex distribution of 41 males and 17 females (ratio of 2.4:1). Overall mean time of presentation was at 18.3 months either post-injury or following onset of symptoms for nontraumatic peripheral nerve problems, with the earliest presentation being 1 day post-obstetric brachial plexus injury in a newborn at birth and the latest being 15 years in 2 patients (one with a left ulnar nerve nodule and the other with a left brachial plexus PNST respectively). The majority of the cases were for brachial plexus injuries (n = 30, 44.1%) comprising 19 adult surgeries and 11 pediatric surgeries. Among the 19 adult surgeries, there were 10 procedures for pan-brachial plexus injuries, 7 for upper brachial plexus injuries and only 2 for lower brachial plexus injuries (**Table 1**). Of the 11 pediatric surgeries, 9 were for obstetric brachial pan-plexus injuries (OBPI—Erb's-Klumpke type) with one of the patients undergoing surgery twice while the remaining 2 were for road traffic accident traumatic injuries (**Table 1**). There were 21 excisions for peripheral nerve sheath tumors of which four were malignant, with one of these three patients requiring surgery twice (**Table 2**). There were 8 peripheral nerve entrapments comprising 3 posterior interosseous nerve entrapments, 3 cubital tunnel syndromes, 1 thoracic outlet syndrome and 1 Guyon's canal entrapment syndrome. The remaining 9 surgeries included repair for 2 patients with penetrating ulnar nerve injury, 2 patients with iatrogenic nerve injuries from PNST surgeries done elsewhere (brachial plexus and common peroneal respectively), and procedures for chronic neuralgia (which included 3 DREZ-otomies, image-guided radiofrequency lesioning, open neurotomy of lateral cutaneous nerve of the right forearm and selective fascicular neurectomy of the left distal ulnar nerve). Among the benign lesions, 12 (57.1%) were benign schwannomas, while the remaining 42.9% consisted of various other lesions. Of note, 3 patients undergoing PNST using the fascicular-sparing subcapsular dissection technique noted post-op sensory deficits or paresthesias which were generally transient and none was noted to have any motor deficits.

Pan-brachial plexus injury (adult) 9 30.0% Upper brachial plexus injury (adult) 7 23.3% Lower brachial plexus injury (adult) 2 6.67% Obstetric brachial plexus injury (OBPI) 10 33.3% Surgically managed Non-obstetric traumatic brachial plexus injuries 2 6.67% Total **30 100.0%**

**Table 1.** Distribution of surgery for adult and pediatric brachial plexus injuries.

**n Percentage**

our outpatient clinics.

130 Treatment of Brachial Plexus Injuries

**3. Results**


**Table 3.** Breakdown of all procedures done for brachial plexus injuries.

**Figure 5.** Summary of various peripheral nerve surgeries done over the five year period under review. Brachial plexus injury repairs and PNST excisions formed the bulk of the procedures.


**4. Discussion**

**4.1. Perculiarities, trend, and pattern**

muscle weakness (**Table 6**).

**4.2. Outcomes**

Majority of the entire 58 patients were first seen at the out-patient clinic, while a few of them presented via the emergency room. Similar to observations in the literature, the more commonly affected anatomic side was the right side (58.5%) compared to 36.9% of the patients who had their problems on the left, with the remaining 4.6% who were mainly Neurofibromatosis-1 patients having bilateral PNSTs. There was a slight male preponderance of 2.4:1 in this study. Most other investigators similarly reported male predominance in their work (**Table 6**). From the observations as shown in the results, the majority of them were injury cases which were generally brachial plexus injuries (n = 30, 44.1%). Among the adult cases, pan-brachial plexus injuries were the commonest (n = 9; 50%), closely followed by upper brachial plexus injuries (n = 7; 38.9%) while lower brachial plexus injuries were the least (n = 2; 11.1%). Most of these presented fairly late (overall average time of presentation was 18.3 months) as a result of considerable length of time required for referral and transfer to our center following occurrence of the injury. As a result, majority of the procedures were done on elective basis instead of as emergencies. A few other factors which were probably responsible for late presentation possibly included poverty, living far away from our institution, initial visitation or consultation to other alternative healers, and sometimes delayed referral from other medical facilities. The follow-up rate at the end of the 2 year period was 95% for adults (**Table 4**) and 91% for the pediatric cases (**Table 5**) of the brachial plexus injury surgeries. The peripheral nerve sheath tumors ranked next in frequency (n = 21, 30.9%). The timing and pattern of presentation of this set of patients did not differ significantly from the nerve injury patients. Similar to the general pattern in the literature [14], the majority of the peripheral nerve tumors were benign. We had only 8 peripheral nerve entrapments while procedures for chronic neuralgia were the fewest (n = 3, 4.4%). Estimated blood loss was negligible in all surgeries except in one case of longstanding left brachial plexus PNST (**Table 6**). The post-operative complications noted in 22.1% of the patients post-operatively were mostly wound infection and post-PNST excision

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Anyone would agree that timing of surgery is very crucial in the ultimate outcome. Yet, in spite of the fairly late presentation in the majority, it is clear from **Tables 4** and **5** that despite the relatively small number of 58 patients in our series, there was generally a steady rise in number of those with marked improvement of functional recovery, with a simultaneous decline in the proportion of "no improvements at all" over the same period. We did more of adult brachial plexus injury repairs and became less enthusiastic about pediatric cases as our practice developed because the adult cases generally benefitted from surgical repair (**Figure 6**). In our personal experience with managing 196 cases of Erb's and Erb's plus palsies, excellent recoveries were possible in majority of cases with just a proper rehabilitation programme consisting

of cerebral retraining and judicious management of co-contracture deformities.

**Table 4.** Summary of outcomes for the adult brachial plexus injury repair.


**Table 5.** Summary of functional outcomes for the pediatric brachial plexus injuries.


**Table 6.** Post-operative complications.

injury repairs and PNST excisions formed the bulk of the procedures. Outcomes at 6 month, 1 year and 2 years post-op are as summarized in **Tables 4** and **5**. Complications following surgery are as shown in **Table 6**.
