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Correspondence Suprascapular nerve block in the management of cancer pain
We read with interest the article by Wassef describing the use of suprascapular nerve block in the management of frozen shoulder (Anaesthesia 1992; 47: 120-4). The use of this block for cancer pain has not been reported previously and we would like to describe its use in the management of shoulder pain due to a solitary metastasis from breast cancer. A 39-year-old woman presented to the Pain Clinic with a 9 month history of pain in the left shoulder. She had undergone a right partial mastectomy for carcinoma of the breast 21 months previously. A local recurrence had subsequently been successfully treated by radiotherapy. X ray and bone scan showed a single destructive deposit in the head of the left humerus consistent with a metastasis. This had also been irradiated, but was unchanged on a bone scan. The shoulder pain was poorly controlled by escalating doses of morphine, naproxen and mefenamic acid, and the patient was severely troubled by nausea and vomiting produced by these drugs. Using a standard technique [ 11, a left diagnostic suprascapular nerve block was performed using 0.5% plain bupivacaine and methylprednisolone. This resulted in complete relief of her pain and she was able to stop taking all analgesics until the following day. Her shoulder pain then returned and she underwent a left suprascapular nerve cryolesion using a Spembly SL 2000 Neurostat with a Lloyd cryoneedle under Image Intensification. Two freezethaw cycles were performed, with each freeze timed at 3 min. The patient was pain free immediately after this procedure and required no further analgesics. She remained
free of pain when followed up at 4 months and at 12 months. Suprascapular nerve block is well recognised in the management of chronic noncancer shoulder pain [ 2 4 ] . The use of this block in cancer pain has not been reported previously and should be considered in patients with isolated deposits in the head of the humerus in whom opioids and other drugs are poorly tolerated [5,6]. Pain Clinic, St. Bartholomew's Hospital,
M. MEYER-WITTING J.M.G. FOSTER
London E C l A 7BE References [I] ERIKSON E. Illustrated handbook in local anaesthesia, 2nd edn. London: Loyd Luke, 1979: 85. [2] CHARLTON JE. Current views on the use of nerve blocking in the relief of chronic pain. In: M SWERDLOW, ed. 2nd edn. The therapy of pain. Lancaster: MTP Press Ltd, 1986: 153. [3] BROWNDE, JAMESDC, ROYS. Pain relief by suprascapular nerve block in gleno-humeral arthritis Scandinavian Journal uJ Rheumatology 1988; 17: 41 1-5. [4] EMERY,P. BOWMNAN S, WEDDERBURN L, GAHAME R. Suprascapular nerve block for chronic shoulder pain in rheumatoid arthritis. British Medical Journal 1989; 299: 1079-804. [5] BONICAJJ. Diagnostic and therapeutic blocks. A reappraisal based on 15 years experience. Anesthesia and Analgesia. 1958; 27: 58-68 [6] LIPTONS. Pain relief in active patients with cancer: the early use of nerve blocks improves the quality of life. British Medical Journal 1989; 298: 37-8.
Suprascapular nerve block. New indications and a safer technique We were interested to read the study on the application of suprascapular nerve block for the management of shoulder pain by Professor Wassef (Anaesthesia 1992; 47: 120-4). We have not been able to identify a previous description of the block with nerve stimulation as part of the technique and would like to add our own observations. Our experience of suprascapular nerve block has been in the management of postoperative pain following open or closed (arthroscopic) shoulder surgery, particularly acromioplasty. We were surprised at the efficacy o f the block in relieving pain in what is a notoriously painful operative site and we undertook a preliminary study of 1 1 patients having shoulder arthroscopy with or without arthroscopic surgery of the acromioclavicular joint. The suprascapular nerve was located in anaesthetised subjects using a Braun Stimuplex peripheral nerve stimulator and 5 cm 20 gauge insulated needle. It is not clear whether Professor Wassef used a short bevel needle, but we feel that this is essential to avoid nerve damage. The surface marking for needle insertion was obtained by drawing a line to divide the length of the spine of the scapula into thirds and drawing a second line perpendicular to the first at the junction of the medial third and lateral two-thirds. The scapular notch lies 1 to 2 cm cranial to the point of intersection. The classical method [I] involves drawing a line to bissect the scapular angle; however, bony landmarks are difficult to palpate in obese or muscular subjects and the spine may be more readily identified than the angle. Professor Wassef mentions that it is not necessary to turn the patient with the anterior approach and this is also true of our posterior approach, when some experience has been obtained. Supraspinatus and/or infraspinatus twitch was observed directly and confirmed by an assistant
supporting the arm with the elbow in flexion, when abduction and external rotation were readily detected. In eight cases the branch to supraspinatus was stimulated and in three, infraspinatus twitch also occurred indicating main trunk stimulation. The nerve was identified at a depth of 1.5-3 cm, which accords with Gordh's description [2]. When muscle twitch was still present at 0.5 rnA and abolished by the injection of 1 ml of local anaesthetic, a further 9 ml of 0.5% bupivacaine with adrenaline 1 :200 000 was injected. The cutaneous distribution of the suprascapular nerve is a variable feature and complete analgesia may require supplementary subcutaneous infiltration. Occasional difficulty in identifying the nerve may be due to pre-existing rotator cuff rupture and supraspinatus atrophy. We consider that this technique minimises the risk of complications (pneumothorax and intravascular injection) and provides a simpler and safer alternative to interscalene or supraclavicular brachial plexus block in the management of this type of postoperative pain. We note that Professor Wassef did not include a control group in his study and this must clearly be an essential part of any more formal assessment of the block. Royal Infirmary. Edinburgh EH3 9YW
J.E. RISDALL G.H. SHARWOOD-SMITH
References [I] Moore D.C. Regional nerve block, 4th edn. Springfield: Charles C. Thomas, 1979. [2] GORDHT. Suprascapular nerve block. In: ERIKSSON E, ed. Illustrated handbook in local anaesthesia. Munksgaard: Copenhagen, 1969: 8 1.
Correspondence Suprascapular nerve block in the management of cancer pain
We read with interest the article by Wassef describing the use of suprascapular nerve block in the management of frozen shoulder (Anaesthesia 1992; 47: 120-4). The use of this block for cancer pain has not been reported previously and we would like to describe its use in the management of shoulder pain due to a solitary metastasis from breast cancer. A 39-year-old woman presented to the Pain Clinic with a 9 month history of pain in the left shoulder. She had undergone a right partial mastectomy for carcinoma of the breast 21 months previously. A local recurrence had subsequently been successfully treated by radiotherapy. X ray and bone scan showed a single destructive deposit in the head of the left humerus consistent with a metastasis. This had also been irradiated, but was unchanged on a bone scan. The shoulder pain was poorly controlled by escalating doses of morphine, naproxen and mefenamic acid, and the patient was severely troubled by nausea and vomiting produced by these drugs. Using a standard technique [ 11, a left diagnostic suprascapular nerve block was performed using 0.5% plain bupivacaine and methylprednisolone. This resulted in complete relief of her pain and she was able to stop taking all analgesics until the following day. Her shoulder pain then returned and she underwent a left suprascapular nerve cryolesion using a Spembly SL 2000 Neurostat with a Lloyd cryoneedle under Image Intensification. Two freezethaw cycles were performed, with each freeze timed at 3 min. The patient was pain free immediately after this procedure and required no further analgesics. She remained
free of pain when followed up at 4 months and at 12 months. Suprascapular nerve block is well recognised in the management of chronic noncancer shoulder pain [ 2 4 ] . The use of this block in cancer pain has not been reported previously and should be considered in patients with isolated deposits in the head of the humerus in whom opioids and other drugs are poorly tolerated [5,6]. Pain Clinic, St. Bartholomew's Hospital,
M. MEYER-WITTING J.M.G. FOSTER
London E C l A 7BE References [I] ERIKSON E. Illustrated handbook in local anaesthesia, 2nd edn. London: Loyd Luke, 1979: 85. [2] CHARLTON JE. Current views on the use of nerve blocking in the relief of chronic pain. In: M SWERDLOW, ed. 2nd edn. The therapy of pain. Lancaster: MTP Press Ltd, 1986: 153. [3] BROWNDE, JAMESDC, ROYS. Pain relief by suprascapular nerve block in gleno-humeral arthritis Scandinavian Journal uJ Rheumatology 1988; 17: 41 1-5. [4] EMERY,P. BOWMNAN S, WEDDERBURN L, GAHAME R. Suprascapular nerve block for chronic shoulder pain in rheumatoid arthritis. British Medical Journal 1989; 299: 1079-804. [5] BONICAJJ. Diagnostic and therapeutic blocks. A reappraisal based on 15 years experience. Anesthesia and Analgesia. 1958; 27: 58-68 [6] LIPTONS. Pain relief in active patients with cancer: the early use of nerve blocks improves the quality of life. British Medical Journal 1989; 298: 37-8.
Suprascapular nerve block. New indications and a safer technique We were interested to read the study on the application of suprascapular nerve block for the management of shoulder pain by Professor Wassef (Anaesthesia 1992; 47: 120-4). We have not been able to identify a previous description of the block with nerve stimulation as part of the technique and would like to add our own observations. Our experience of suprascapular nerve block has been in the management of postoperative pain following open or closed (arthroscopic) shoulder surgery, particularly acromioplasty. We were surprised at the efficacy o f the block in relieving pain in what is a notoriously painful operative site and we undertook a preliminary study of 1 1 patients having shoulder arthroscopy with or without arthroscopic surgery of the acromioclavicular joint. The suprascapular nerve was located in anaesthetised subjects using a Braun Stimuplex peripheral nerve stimulator and 5 cm 20 gauge insulated needle. It is not clear whether Professor Wassef used a short bevel needle, but we feel that this is essential to avoid nerve damage. The surface marking for needle insertion was obtained by drawing a line to divide the length of the spine of the scapula into thirds and drawing a second line perpendicular to the first at the junction of the medial third and lateral two-thirds. The scapular notch lies 1 to 2 cm cranial to the point of intersection. The classical method [I] involves drawing a line to bissect the scapular angle; however, bony landmarks are difficult to palpate in obese or muscular subjects and the spine may be more readily identified than the angle. Professor Wassef mentions that it is not necessary to turn the patient with the anterior approach and this is also true of our posterior approach, when some experience has been obtained. Supraspinatus and/or infraspinatus twitch was observed directly and confirmed by an assistant
supporting the arm with the elbow in flexion, when abduction and external rotation were readily detected. In eight cases the branch to supraspinatus was stimulated and in three, infraspinatus twitch also occurred indicating main trunk stimulation. The nerve was identified at a depth of 1.5-3 cm, which accords with Gordh's description [2]. When muscle twitch was still present at 0.5 rnA and abolished by the injection of 1 ml of local anaesthetic, a further 9 ml of 0.5% bupivacaine with adrenaline 1 :200 000 was injected. The cutaneous distribution of the suprascapular nerve is a variable feature and complete analgesia may require supplementary subcutaneous infiltration. Occasional difficulty in identifying the nerve may be due to pre-existing rotator cuff rupture and supraspinatus atrophy. We consider that this technique minimises the risk of complications (pneumothorax and intravascular injection) and provides a simpler and safer alternative to interscalene or supraclavicular brachial plexus block in the management of this type of postoperative pain. We note that Professor Wassef did not include a control group in his study and this must clearly be an essential part of any more formal assessment of the block. Royal Infirmary. Edinburgh EH3 9YW
J.E. RISDALL G.H. SHARWOOD-SMITH
References [I] Moore D.C. Regional nerve block, 4th edn. Springfield: Charles C. Thomas, 1979. [2] GORDHT. Suprascapular nerve block. In: ERIKSSON E, ed. Illustrated handbook in local anaesthesia. Munksgaard: Copenhagen, 1969: 8 1.
